Merge pull request 'ui: plan 01-27 done' (#1) from ai/ui-client into main

Reviewed-on: https://gitea.dev/developer/galaxy-game/pulls/1

.gitattributes

@@ -1 +1,5 @@
 *.wasm binary
+*.ts linguist-language=TypeScript
+*.ts linguist-detectable=true
+*.ts linguist-vendored=false
+*.ts linguist-generated=false

backend/README.md

@@ -333,15 +333,42 @@ cannot guarantee.
 | `runtime.image_pull_failed`         | admin email   | `game_id`, `image_ref`                                   |
 | `runtime.container_start_failed`    | admin email   | `game_id`                                                |
 | `runtime.start_config_invalid`      | admin email   | `game_id`, `reason`                                      |
+| `game.turn.ready`                   | push          | `game_id`, `turn`                                        |
+| `game.paused`                       | push          | `game_id`, `turn`, `reason`                              |
 
 Admin-channel kinds (`runtime.*`) deliver email to
 `BACKEND_NOTIFICATION_ADMIN_EMAIL`; when the variable is empty, those
 routes land in `notification_routes` with `status='skipped'` and the
 operator log line records the configuration miss.
 
-`game.*` (`game.started`, `game.turn.ready`, `game.generation.failed`,
-`game.finished`) and `mail.dead_lettered` are reserved kinds without a
-producer in the catalog; adding them is an additive change to the
+`game.turn.ready` and `game.paused` are emitted by
+`lobby.Service.OnRuntimeSnapshot`
+(`backend/internal/lobby/runtime_hooks.go`):
+
+- `game.turn.ready` fires whenever the engine's `current_turn`
+  advances. Idempotency key `turn-ready:<game_id>:<turn>`, JSON
+  payload `{game_id, turn}`.
+- `game.paused` fires whenever the same hook flips the game
+  `running → paused` because a runtime snapshot landed with
+  `engine_unreachable` / `generation_failed`. Idempotency key
+  `paused:<game_id>:<turn>`, JSON payload
+  `{game_id, turn, reason}` (reason carries the runtime status
+  that triggered the transition). The runtime scheduler
+  (`backend/internal/runtime/scheduler.go`) forwards the failing
+  snapshot through `Service.publishFailureSnapshot` so a single
+  failing tick reliably reaches lobby.
+
+Both kinds target every active membership and route through the
+push channel only — per-turn / per-pause email would be spam — so
+the UI's signed `SubscribeEvents` stream
+(`ui/frontend/src/api/events.svelte.ts`) is the sole delivery
+path. The order tab consumes them via
+`OrderDraftStore.resetForNewTurn` / `markPaused`
+(`ui/docs/sync-protocol.md`).
+
+The remaining `game.*` (`game.started`, `game.generation.failed`,
+`game.finished`) and `mail.dead_lettered` are reserved kinds without
+a producer in the catalog; adding them is an additive change to the
 catalog vocabulary and the migration CHECK constraint.
 
 Templates ship in English only; localisation belongs to clients that

backend/internal/engineclient/client.go

@@ -26,6 +26,7 @@ const (
 	pathPlayerCommand   = "/api/v1/command"
 	pathPlayerOrder     = "/api/v1/order"
 	pathPlayerReport    = "/api/v1/report"
+	pathPlayerBattle    = "/api/v1/battle"
 	pathHealthz         = "/healthz"
 )
 
@@ -269,6 +270,41 @@ func (c *Client) GetReport(ctx context.Context, baseURL, raceName string, turn i
 	}
 }
 
+// FetchBattle calls `GET /api/v1/battle/<turn>/<battleID>` and returns
+// the engine response body verbatim alongside the engine status code.
+// 200 carries the BattleReport JSON; 404 means the battle is unknown
+// and the body may be empty. Other 4xx statuses come back wrapped in
+// ErrEngineValidation, everything else in ErrEngineUnreachable.
+func (c *Client) FetchBattle(ctx context.Context, baseURL string, turn int, battleID string) (json.RawMessage, int, error) {
+	if err := validateBaseURL(baseURL); err != nil {
+		return nil, 0, err
+	}
+	if turn < 0 {
+		return nil, 0, fmt.Errorf("engineclient battle get: turn must not be negative, got %d", turn)
+	}
+	if strings.TrimSpace(battleID) == "" {
+		return nil, 0, errors.New("engineclient battle get: battle id must not be empty")
+	}
+	target := baseURL + pathPlayerBattle + "/" + strconv.Itoa(turn) + "/" + url.PathEscape(battleID)
+	body, status, doErr := c.doRequest(ctx, http.MethodGet, target, nil, c.probeTimeout)
+	if doErr != nil {
+		return nil, 0, fmt.Errorf("%w: engine battle get: %w", ErrEngineUnreachable, doErr)
+	}
+	switch status {
+	case http.StatusOK:
+		if len(body) == 0 {
+			return nil, status, fmt.Errorf("%w: engine battle get: empty response body", ErrEngineProtocolViolation)
+		}
+		return json.RawMessage(body), status, nil
+	case http.StatusNotFound:
+		return nil, status, nil
+	case http.StatusBadRequest, http.StatusConflict:
+		return json.RawMessage(body), status, fmt.Errorf("%w: engine battle get: %s", ErrEngineValidation, summariseEngineError(body, status))
+	default:
+		return nil, status, fmt.Errorf("%w: engine battle get: %s", ErrEngineUnreachable, summariseEngineError(body, status))
+	}
+}
+
 // Healthz calls `GET /healthz`. Returns nil on 2xx.
 func (c *Client) Healthz(ctx context.Context, baseURL string) error {
 	if err := validateBaseURL(baseURL); err != nil {

backend/internal/engineclient/client_test.go

@@ -257,6 +257,63 @@ func TestClientGetOrderRejectsBadInput(t *testing.T) {
 	}
 }
 
+func TestClientFetchBattleForwardsPath(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			t.Fatalf("unexpected method: %s", r.Method)
+		}
+		want := pathPlayerBattle + "/3/" + "11111111-1111-1111-1111-111111111111"
+		if r.URL.Path != want {
+			t.Fatalf("path = %q, want %q", r.URL.Path, want)
+		}
+		_, _ = w.Write([]byte(`{"id":"11111111-1111-1111-1111-111111111111","planet":4}`))
+	}))
+	t.Cleanup(srv.Close)
+
+	cli := newTestClient(t, srv)
+	body, status, err := cli.FetchBattle(context.Background(), srv.URL, 3, "11111111-1111-1111-1111-111111111111")
+	if err != nil {
+		t.Fatalf("FetchBattle: %v", err)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("status = %d", status)
+	}
+	if !strings.Contains(string(body), `"planet":4`) {
+		t.Fatalf("body = %s", body)
+	}
+}
+
+func TestClientFetchBattleNotFound(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+	}))
+	t.Cleanup(srv.Close)
+
+	cli := newTestClient(t, srv)
+	body, status, err := cli.FetchBattle(context.Background(), srv.URL, 0, "11111111-1111-1111-1111-111111111111")
+	if err != nil {
+		t.Fatalf("FetchBattle: %v", err)
+	}
+	if status != http.StatusNotFound {
+		t.Fatalf("status = %d", status)
+	}
+	if body != nil {
+		t.Fatalf("expected nil body on 404, got %s", body)
+	}
+}
+
+func TestClientFetchBattleRejectsBadInput(t *testing.T) {
+	cli := newTestClient(t, httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		t.Fatal("server must not be hit on bad input")
+	})))
+	if _, _, err := cli.FetchBattle(context.Background(), "http://example.com", -1, "11111111-1111-1111-1111-111111111111"); err == nil {
+		t.Fatal("expected error on negative turn")
+	}
+	if _, _, err := cli.FetchBattle(context.Background(), "http://example.com", 0, ""); err == nil {
+		t.Fatal("expected error on empty battle id")
+	}
+}
+
 func TestClientHealthzSuccess(t *testing.T) {
 	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		if r.URL.Path != pathHealthz {

backend/internal/lobby/lobby.go

@@ -109,6 +109,8 @@ const (
 	NotificationLobbyRaceNameRegistered = "lobby.race_name.registered"
 	NotificationLobbyRaceNamePending = "lobby.race_name.pending"
 	NotificationLobbyRaceNameExpired = "lobby.race_name.expired"
+	NotificationGameTurnReady = "game.turn.ready"
+	NotificationGamePaused = "game.paused"
 )
 
 // Deps aggregates every collaborator the lobby Service depends on.

backend/internal/lobby/runtime_hooks.go

@@ -30,12 +30,14 @@ func (s *Service) OnRuntimeSnapshot(ctx context.Context, gameID uuid.UUID, snaps
 	if err != nil {
 		return err
 	}
+	prevTurn := game.RuntimeSnapshot.CurrentTurn
 	merged := mergeRuntimeSnapshot(game.RuntimeSnapshot, snapshot)
 	now := s.deps.Now().UTC()
 	updated, err := s.deps.Store.UpdateGameRuntimeSnapshot(ctx, gameID, merged, now)
 	if err != nil {
 		return err
 	}
+	transitionedToPaused := false
 	if next, transition := nextStatusFromSnapshot(updated.Status, snapshot); transition {
 		switch next {
 		case GameStatusFinished:
@@ -52,12 +54,115 @@ func (s *Service) OnRuntimeSnapshot(ctx context.Context, gameID uuid.UUID, snaps
 				return err
 			}
 			updated = rec
+			if next == GameStatusPaused {
+				transitionedToPaused = true
+			}
 		}
 	}
 	s.deps.Cache.PutGame(updated)
+	if merged.CurrentTurn > prevTurn {
+		s.publishTurnReady(ctx, gameID, merged.CurrentTurn)
+	}
+	if transitionedToPaused {
+		s.publishGamePaused(ctx, gameID, merged.CurrentTurn, snapshot.RuntimeStatus)
+	}
 	return nil
 }
 
+// publishTurnReady fans out a `game.turn.ready` notification to every
+// active member of the game once the engine reports a new
+// `current_turn`. The intent is best-effort: a publisher failure is
+// logged at warn level (matching the rest of OnRuntimeSnapshot's
+// notification calls) and does not abort the snapshot bookkeeping.
+// Idempotency is anchored on (game_id, turn), so a duplicate snapshot
+// for the same turn collapses into a single notification at the
+// notification.Submit boundary.
+func (s *Service) publishTurnReady(ctx context.Context, gameID uuid.UUID, turn int32) {
+	memberships, err := s.deps.Store.ListMembershipsForGame(ctx, gameID)
+	if err != nil {
+		s.deps.Logger.Warn("turn-ready notification: list memberships failed",
+			zap.String("game_id", gameID.String()),
+			zap.Int32("turn", turn),
+			zap.Error(err))
+		return
+	}
+	recipients := make([]uuid.UUID, 0, len(memberships))
+	for _, m := range memberships {
+		if m.Status != MembershipStatusActive {
+			continue
+		}
+		recipients = append(recipients, m.UserID)
+	}
+	if len(recipients) == 0 {
+		return
+	}
+	intent := LobbyNotification{
+		Kind:           NotificationGameTurnReady,
+		IdempotencyKey: fmt.Sprintf("turn-ready:%s:%d", gameID, turn),
+		Recipients:     recipients,
+		Payload: map[string]any{
+			"game_id": gameID.String(),
+			"turn":    turn,
+		},
+	}
+	if pubErr := s.deps.Notification.PublishLobbyEvent(ctx, intent); pubErr != nil {
+		s.deps.Logger.Warn("turn-ready notification failed",
+			zap.String("game_id", gameID.String()),
+			zap.Int32("turn", turn),
+			zap.Error(pubErr))
+	}
+}
+
+// publishGamePaused fans out a `game.paused` notification to every
+// active member of the game when the lobby flips the game to
+// `paused` in reaction to a runtime snapshot (typically a failed
+// turn generation). The intent is best-effort: a publisher failure
+// is logged at warn level and does not abort the snapshot
+// bookkeeping. Idempotency is anchored on (game_id, turn) so a
+// repeated `generation_failed` snapshot for the same turn collapses
+// into a single notification at the notification.Submit boundary.
+//
+// reason carries the raw runtime status that triggered the pause
+// (`engine_unreachable` / `generation_failed`); the UI displays a
+// status-agnostic banner today but the payload is preserved so a
+// future revision of the order tab can differentiate.
+func (s *Service) publishGamePaused(ctx context.Context, gameID uuid.UUID, turn int32, reason string) {
+	memberships, err := s.deps.Store.ListMembershipsForGame(ctx, gameID)
+	if err != nil {
+		s.deps.Logger.Warn("game-paused notification: list memberships failed",
+			zap.String("game_id", gameID.String()),
+			zap.Int32("turn", turn),
+			zap.Error(err))
+		return
+	}
+	recipients := make([]uuid.UUID, 0, len(memberships))
+	for _, m := range memberships {
+		if m.Status != MembershipStatusActive {
+			continue
+		}
+		recipients = append(recipients, m.UserID)
+	}
+	if len(recipients) == 0 {
+		return
+	}
+	intent := LobbyNotification{
+		Kind:           NotificationGamePaused,
+		IdempotencyKey: fmt.Sprintf("paused:%s:%d", gameID, turn),
+		Recipients:     recipients,
+		Payload: map[string]any{
+			"game_id": gameID.String(),
+			"turn":    turn,
+			"reason":  reason,
+		},
+	}
+	if pubErr := s.deps.Notification.PublishLobbyEvent(ctx, intent); pubErr != nil {
+		s.deps.Logger.Warn("game-paused notification failed",
+			zap.String("game_id", gameID.String()),
+			zap.Int32("turn", turn),
+			zap.Error(pubErr))
+	}
+}
+
 // OnGameFinished completes the game lifecycle: marks the game as
 // `finished`, evaluates capable-finish per active member, and
 // transitions reservation rows to either `pending_registration`
@@ -230,13 +335,28 @@ func mergeRuntimeSnapshot(prev, next RuntimeSnapshot) RuntimeSnapshot {
 // nextStatusFromSnapshot maps the runtime-reported runtime status into
 // a lobby status transition. Returns (next, true) when the lobby
 // status must change; (current, false) otherwise.
+//
+// The map intentionally distinguishes the pre-running boot path
+// (`starting → start_failed`) from the in-flight failure path
+// (`running → paused`). Paused games can be resumed by the admin via
+// the explicit `/resume` transition; the runtime keeps the engine
+// container alive, the scheduler short-circuits ticks while paused,
+// and any user-games command/order is rejected by the order handler
+// with `turn_already_closed` until the game resumes.
 func nextStatusFromSnapshot(currentStatus string, snapshot RuntimeSnapshot) (string, bool) {
 	switch snapshot.RuntimeStatus {
 	case "running":
 		if currentStatus == GameStatusStarting {
 			return GameStatusRunning, true
 		}
-	case "engine_unreachable", "start_failed", "generation_failed":
+	case "engine_unreachable", "generation_failed":
+		if currentStatus == GameStatusStarting {
+			return GameStatusStartFailed, true
+		}
+		if currentStatus == GameStatusRunning {
+			return GameStatusPaused, true
+		}
+	case "start_failed":
 		if currentStatus == GameStatusStarting {
 			return GameStatusStartFailed, true
 		}

backend/internal/lobby/runtime_hooks_test.go

@@ -0,0 +1,207 @@
+package lobby_test
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"sync"
+	"testing"
+	"time"
+
+	"galaxy/backend/internal/config"
+	"galaxy/backend/internal/lobby"
+
+	"github.com/google/uuid"
+)
+
+// capturingPublisher records every `LobbyNotification` intent that the
+// lobby service emits, so a test can assert the producer side without
+// running the real notification.Submit pipeline.
+type capturingPublisher struct {
+	mu    sync.Mutex
+	items []lobby.LobbyNotification
+}
+
+func (p *capturingPublisher) PublishLobbyEvent(_ context.Context, ev lobby.LobbyNotification) error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.items = append(p.items, ev)
+	return nil
+}
+
+func (p *capturingPublisher) byKind(kind string) []lobby.LobbyNotification {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	out := make([]lobby.LobbyNotification, 0, len(p.items))
+	for _, ev := range p.items {
+		if ev.Kind == kind {
+			out = append(out, ev)
+		}
+	}
+	return out
+}
+
+// newServiceWithPublisher mirrors `newServiceForTest` but lets the
+// caller inject a custom NotificationPublisher; the runtime-hooks
+// emit path needs to observe intents directly.
+func newServiceWithPublisher(t *testing.T, db *sql.DB, now func() time.Time, max int32, publisher lobby.NotificationPublisher) *lobby.Service {
+	t.Helper()
+	store := lobby.NewStore(db)
+	cache := lobby.NewCache()
+	if err := cache.Warm(context.Background(), store); err != nil {
+		t.Fatalf("warm cache: %v", err)
+	}
+	svc, err := lobby.NewService(lobby.Deps{
+		Store:        store,
+		Cache:        cache,
+		Notification: publisher,
+		Entitlement:  stubEntitlement{max: max},
+		Config: config.LobbyConfig{
+			SweeperInterval:        time.Second,
+			PendingRegistrationTTL: time.Hour,
+			InviteDefaultTTL:       time.Hour,
+		},
+		Now: now,
+	})
+	if err != nil {
+		t.Fatalf("new service: %v", err)
+	}
+	return svc
+}
+
+// TestOnRuntimeSnapshotEmitsTurnReady verifies that an engine snapshot
+// advancing `current_turn` fans out a `game.turn.ready` intent to every
+// active member, that the idempotency key is anchored on (game_id, turn),
+// and that a snapshot with the same turn does not re-emit.
+func TestOnRuntimeSnapshotEmitsTurnReady(t *testing.T) {
+	db := startPostgres(t)
+	now := time.Now().UTC()
+	clock := func() time.Time { return now }
+	publisher := &capturingPublisher{}
+	svc := newServiceWithPublisher(t, db, clock, 5, publisher)
+
+	owner := uuid.New()
+	seedAccount(t, db, owner)
+
+	game, err := svc.CreateGame(context.Background(), lobby.CreateGameInput{
+		OwnerUserID:         &owner,
+		Visibility:          lobby.VisibilityPrivate,
+		GameName:            "Turn-Ready Fan-Out",
+		MinPlayers:          1,
+		MaxPlayers:          4,
+		StartGapHours:       1,
+		StartGapPlayers:     1,
+		EnrollmentEndsAt:    now.Add(time.Hour),
+		TurnSchedule:        "0 0 * * *",
+		TargetEngineVersion: "1.0.0",
+	})
+	if err != nil {
+		t.Fatalf("create game: %v", err)
+	}
+	if _, err := svc.OpenEnrollment(context.Background(), &owner, false, game.GameID); err != nil {
+		t.Fatalf("open enrollment: %v", err)
+	}
+
+	// Seed two active members through the store so the test focuses on
+	// the runtime hook, not the membership state machine.
+	store := lobby.NewStore(db)
+	canonicalPolicy, err := lobby.NewPolicy()
+	if err != nil {
+		t.Fatalf("new policy: %v", err)
+	}
+	memberA := uuid.New()
+	memberB := uuid.New()
+	seedAccount(t, db, memberA)
+	seedAccount(t, db, memberB)
+	for i, m := range []uuid.UUID{memberA, memberB} {
+		race := fmt.Sprintf("Race%d", i+1)
+		canonical, err := canonicalPolicy.Canonical(race)
+		if err != nil {
+			t.Fatalf("canonical %q: %v", race, err)
+		}
+		if _, err := db.ExecContext(context.Background(), `
+			INSERT INTO backend.memberships (
+				membership_id, game_id, user_id, race_name, canonical_key, status
+			) VALUES ($1, $2, $3, $4, $5, 'active')
+		`, uuid.New(), game.GameID, m, race, string(canonical)); err != nil {
+			t.Fatalf("seed membership %s: %v", m, err)
+		}
+	}
+	if err := svc.Cache().Warm(context.Background(), store); err != nil {
+		t.Fatalf("re-warm cache: %v", err)
+	}
+	if _, err := svc.ReadyToStart(context.Background(), &owner, false, game.GameID); err != nil {
+		t.Fatalf("ready-to-start: %v", err)
+	}
+	if _, err := svc.Start(context.Background(), &owner, false, game.GameID); err != nil {
+		t.Fatalf("start: %v", err)
+	}
+
+	// First snapshot: prev=0, current_turn=1 → emit on the very first
+	// turn after the engine starts producing.
+	if err := svc.OnRuntimeSnapshot(context.Background(), game.GameID, lobby.RuntimeSnapshot{
+		CurrentTurn:   1,
+		RuntimeStatus: "running",
+	}); err != nil {
+		t.Fatalf("on-runtime-snapshot 1: %v", err)
+	}
+	intents := publisher.byKind(lobby.NotificationGameTurnReady)
+	if len(intents) != 1 {
+		t.Fatalf("after turn 1 want 1 turn-ready intent, got %d", len(intents))
+	}
+	first := intents[0]
+	wantKey := fmt.Sprintf("turn-ready:%s:1", game.GameID)
+	if first.IdempotencyKey != wantKey {
+		t.Errorf("turn 1 idempotency key = %q, want %q", first.IdempotencyKey, wantKey)
+	}
+	if got := first.Payload["turn"]; got != int32(1) {
+		t.Errorf("turn 1 payload turn = %v, want 1", got)
+	}
+	if got := first.Payload["game_id"]; got != game.GameID.String() {
+		t.Errorf("turn 1 payload game_id = %v, want %s", got, game.GameID)
+	}
+	if len(first.Recipients) != 2 {
+		t.Errorf("turn 1 recipients = %d, want 2", len(first.Recipients))
+	}
+	recipientSet := map[uuid.UUID]struct{}{}
+	for _, r := range first.Recipients {
+		recipientSet[r] = struct{}{}
+	}
+	if _, ok := recipientSet[memberA]; !ok {
+		t.Errorf("turn 1 missing memberA in recipients")
+	}
+	if _, ok := recipientSet[memberB]; !ok {
+		t.Errorf("turn 1 missing memberB in recipients")
+	}
+
+	// Same turn re-delivered (duplicate snapshot, gateway replay) must
+	// not re-emit at the lobby layer: prev catches up to merged.
+	if err := svc.OnRuntimeSnapshot(context.Background(), game.GameID, lobby.RuntimeSnapshot{
+		CurrentTurn:   1,
+		RuntimeStatus: "running",
+	}); err != nil {
+		t.Fatalf("on-runtime-snapshot 1 replay: %v", err)
+	}
+	if got := len(publisher.byKind(lobby.NotificationGameTurnReady)); got != 1 {
+		t.Fatalf("after duplicate turn 1 want 1 intent, got %d", got)
+	}
+
+	// Next turn advances → second emit with key anchored on turn 2.
+	if err := svc.OnRuntimeSnapshot(context.Background(), game.GameID, lobby.RuntimeSnapshot{
+		CurrentTurn:   2,
+		RuntimeStatus: "running",
+	}); err != nil {
+		t.Fatalf("on-runtime-snapshot 2: %v", err)
+	}
+	intents = publisher.byKind(lobby.NotificationGameTurnReady)
+	if len(intents) != 2 {
+		t.Fatalf("after turn 2 want 2 turn-ready intents, got %d", len(intents))
+	}
+	wantKey2 := fmt.Sprintf("turn-ready:%s:2", game.GameID)
+	if intents[1].IdempotencyKey != wantKey2 {
+		t.Errorf("turn 2 idempotency key = %q, want %q", intents[1].IdempotencyKey, wantKey2)
+	}
+	if got := intents[1].Payload["turn"]; got != int32(2) {
+		t.Errorf("turn 2 payload turn = %v, want 2", got)
+	}
+}

backend/internal/lobby/runtime_hooks_unit_test.go

@@ -0,0 +1,127 @@
+package lobby
+
+import "testing"
+
+// TestNextStatusFromSnapshot covers the pure status-mapping function
+// that drives `OnRuntimeSnapshot`'s lifecycle transitions. The Phase
+// 25 contribution is the `running → paused` branch on
+// `engine_unreachable` / `generation_failed`: the order handler relies
+// on the `paused` game status to reject late submits with
+// `turn_already_closed`.
+func TestNextStatusFromSnapshot(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name          string
+		currentStatus string
+		runtimeStatus string
+		wantStatus    string
+		wantTransit   bool
+	}{
+		{
+			name:          "starting then running flips to running",
+			currentStatus: GameStatusStarting,
+			runtimeStatus: "running",
+			wantStatus:    GameStatusRunning,
+			wantTransit:   true,
+		},
+		{
+			name:          "running on running snapshot does not transit",
+			currentStatus: GameStatusRunning,
+			runtimeStatus: "running",
+			wantStatus:    GameStatusRunning,
+			wantTransit:   false,
+		},
+		{
+			name:          "starting then engine_unreachable flips to start_failed",
+			currentStatus: GameStatusStarting,
+			runtimeStatus: "engine_unreachable",
+			wantStatus:    GameStatusStartFailed,
+			wantTransit:   true,
+		},
+		{
+			name:          "starting then generation_failed flips to start_failed",
+			currentStatus: GameStatusStarting,
+			runtimeStatus: "generation_failed",
+			wantStatus:    GameStatusStartFailed,
+			wantTransit:   true,
+		},
+		{
+			name:          "running then engine_unreachable flips to paused",
+			currentStatus: GameStatusRunning,
+			runtimeStatus: "engine_unreachable",
+			wantStatus:    GameStatusPaused,
+			wantTransit:   true,
+		},
+		{
+			name:          "running then generation_failed flips to paused",
+			currentStatus: GameStatusRunning,
+			runtimeStatus: "generation_failed",
+			wantStatus:    GameStatusPaused,
+			wantTransit:   true,
+		},
+		{
+			name:          "paused stays paused on repeated failed snapshot",
+			currentStatus: GameStatusPaused,
+			runtimeStatus: "generation_failed",
+			wantStatus:    GameStatusPaused,
+			wantTransit:   false,
+		},
+		{
+			name:          "starting then start_failed flips to start_failed",
+			currentStatus: GameStatusStarting,
+			runtimeStatus: "start_failed",
+			wantStatus:    GameStatusStartFailed,
+			wantTransit:   true,
+		},
+		{
+			name:          "running ignores start_failed",
+			currentStatus: GameStatusRunning,
+			runtimeStatus: "start_failed",
+			wantStatus:    GameStatusRunning,
+			wantTransit:   false,
+		},
+		{
+			name:          "running on finished flips to finished",
+			currentStatus: GameStatusRunning,
+			runtimeStatus: "finished",
+			wantStatus:    GameStatusFinished,
+			wantTransit:   true,
+		},
+		{
+			name:          "finished stays finished on finished snapshot",
+			currentStatus: GameStatusFinished,
+			runtimeStatus: "finished",
+			wantStatus:    GameStatusFinished,
+			wantTransit:   false,
+		},
+		{
+			name:          "cancelled stays cancelled on finished snapshot",
+			currentStatus: GameStatusCancelled,
+			runtimeStatus: "finished",
+			wantStatus:    GameStatusCancelled,
+			wantTransit:   false,
+		},
+		{
+			name:          "paused on stopped snapshot flips to finished",
+			currentStatus: GameStatusPaused,
+			runtimeStatus: "stopped",
+			wantStatus:    GameStatusFinished,
+			wantTransit:   true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			got, transit := nextStatusFromSnapshot(tt.currentStatus, RuntimeSnapshot{
+				RuntimeStatus: tt.runtimeStatus,
+			})
+			if got != tt.wantStatus {
+				t.Errorf("status = %q, want %q", got, tt.wantStatus)
+			}
+			if transit != tt.wantTransit {
+				t.Errorf("transit = %v, want %v", transit, tt.wantTransit)
+			}
+		})
+	}
+}

backend/internal/notification/catalog.go

@@ -17,6 +17,8 @@ const (
 	KindRuntimeImagePullFailed = "runtime.image_pull_failed"
 	KindRuntimeContainerStartFailed = "runtime.container_start_failed"
 	KindRuntimeStartConfigInvalid = "runtime.start_config_invalid"
+	KindGameTurnReady = "game.turn.ready"
+	KindGamePaused = "game.paused"
 )
 
 // CatalogEntry describes the per-kind delivery policy: which channels
@@ -95,6 +97,12 @@ var catalog = map[string]CatalogEntry{
 		Admin: true,
 		MailTemplateID: KindRuntimeStartConfigInvalid,
 	},
+	KindGameTurnReady: {
+		Channels: []string{ChannelPush},
+	},
+	KindGamePaused: {
+		Channels: []string{ChannelPush},
+	},
 }
 
 // LookupCatalog returns the per-kind policy and a boolean reporting
@@ -123,5 +131,7 @@ func SupportedKinds() []string {
 		KindRuntimeImagePullFailed,
 		KindRuntimeContainerStartFailed,
 		KindRuntimeStartConfigInvalid,
+		KindGameTurnReady,
+		KindGamePaused,
 	}
 }

backend/internal/notification/catalog_test.go

@@ -39,6 +39,8 @@ func TestCatalogChannels(t *testing.T) {
 		KindRuntimeImagePullFailed:      {ChannelEmail},
 		KindRuntimeContainerStartFailed: {ChannelEmail},
 		KindRuntimeStartConfigInvalid:   {ChannelEmail},
+		KindGameTurnReady:               {ChannelPush},
+		KindGamePaused:                  {ChannelPush},
 	}
 	for kind, want := range expect {
 		entry, ok := LookupCatalog(kind)

backend/internal/notification/events_test.go

@@ -9,9 +9,31 @@ import (
 	"github.com/google/uuid"
 )
 
+// jsonFriendlyKinds lists catalog kinds whose payload is small and
+// stable enough that the gateway-bound encoding stays JSON instead of
+// FlatBuffers. The default for new producers is still FB; declaring a
+// kind here is a deliberate decision baked into the build target's
+// payload contract.
+//
+// `game.turn.ready` ships `{game_id, turn}` only, the UI parses it
+// inline in `routes/games/[id]/+layout.svelte` (Phase 24), and no
+// other consumer reads the payload — adopting the FB encoder would
+// require a new TS notification stub set and the regen tooling for
+// `pkg/schema/fbs/notification.fbs` without buying anything.
+//
+// `game.paused` (Phase 25) follows the same JSON-friendly contract:
+// payload is `{game_id, turn, reason}` consumed by the same in-game
+// shell layout, so there is no value in dragging a FB schema in for
+// one consumer.
+var jsonFriendlyKinds = map[string]bool{
+	KindGameTurnReady: true,
+	KindGamePaused:    true,
+}
+
 // TestBuildClientPushEventCoversCatalog asserts that every catalog kind
-// returns a typed FB event (preMarshaledEvent) and that an unknown kind
-// falls through to the JSON safety net.
+// is exercised by this test, that FB-typed kinds return a
+// `preMarshaledEvent`, and that JSON-friendly kinds (see
+// `jsonFriendlyKinds` above) return a `push.JSONEvent`.
 func TestBuildClientPushEventCoversCatalog(t *testing.T) {
 	t.Parallel()
 
@@ -57,6 +79,15 @@ func TestBuildClientPushEventCoversCatalog(t *testing.T) {
 			"game_id": gameID.String(),
 			"reason":  "missing engine version",
 		}},
+		{"game turn ready", KindGameTurnReady, map[string]any{
+			"game_id": gameID.String(),
+			"turn":    int32(7),
+		}},
+		{"game paused", KindGamePaused, map[string]any{
+			"game_id": gameID.String(),
+			"turn":    int32(7),
+			"reason":  "generation_failed",
+		}},
 	}
 
 	seenKinds := map[string]bool{}
@@ -78,8 +109,10 @@ func TestBuildClientPushEventCoversCatalog(t *testing.T) {
 			if len(bytes) == 0 {
 				t.Fatalf("Marshal returned empty bytes")
 			}
-			if _, isJSON := event.(push.JSONEvent); isJSON {
-				t.Fatalf("expected typed FB event for %s, got JSONEvent", tt.kind)
+			_, isJSON := event.(push.JSONEvent)
+			wantJSON := jsonFriendlyKinds[tt.kind]
+			if isJSON != wantJSON {
+				t.Fatalf("kind %s: JSONEvent=%v, want JSONEvent=%v", tt.kind, isJSON, wantJSON)
 			}
 		})
 		seenKinds[tt.kind] = true

backend/internal/postgres/migrations/00001_init.sql

@@ -605,7 +605,8 @@ CREATE TABLE notifications (
             'lobby.race_name.registered', 'lobby.race_name.pending',
             'lobby.race_name.expired',
             'runtime.image_pull_failed', 'runtime.container_start_failed',
-            'runtime.start_config_invalid'
+            'runtime.start_config_invalid',
+            'game.turn.ready', 'game.paused'
         ))
 );
 

backend/internal/runtime/errors.go

@@ -42,4 +42,23 @@ var (
 	// ErrShutdown means the runtime service has stopped accepting
 	// work because the parent context was cancelled.
 	ErrShutdown = errors.New("runtime: shutting down")
+
+	// ErrTurnAlreadyClosed reports that the runtime is currently
+	// producing a turn — runtime status is `generation_in_progress`
+	// — and the engine is not accepting writes for the closing
+	// turn. Handlers map this to HTTP 409 with httperr code
+	// `turn_already_closed`; the UI shows a conflict banner and
+	// waits for the next `game.turn.ready` push.
+	ErrTurnAlreadyClosed = errors.New("runtime: turn already closed")
+
+	// ErrGamePaused reports that the game is not in a state that
+	// accepts user-games commands or orders: the runtime row
+	// carries `paused = true`, or the runtime status lands on any
+	// terminal value (`engine_unreachable`, `generation_failed`,
+	// `stopped`, `finished`, `removed`), or the game has not yet
+	// finished bootstrapping (`starting`). Handlers map this to
+	// HTTP 409 with httperr code `game_paused`; the UI surfaces a
+	// pause banner and waits for an admin resume or a fresh
+	// snapshot.
+	ErrGamePaused = errors.New("runtime: game paused")
 )

backend/internal/runtime/orders_accept_test.go

@@ -0,0 +1,82 @@
+package runtime
+
+import (
+	"errors"
+	"testing"
+)
+
+// TestOrdersAcceptStatus pins down the Phase 25 pre-check that
+// gates the user-games command/order handlers against the runtime
+// record. The decision must distinguish a turn cutoff (engine is
+// producing) from a paused game so the UI can surface the right
+// banner; all other non-running runtime statuses collapse into
+// `ErrGamePaused`.
+func TestOrdersAcceptStatus(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name string
+		rec  RuntimeRecord
+		want error
+	}{
+		{
+			name: "running and not paused accepts orders",
+			rec:  RuntimeRecord{Status: RuntimeStatusRunning, Paused: false},
+			want: nil,
+		},
+		{
+			name: "running but paused returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusRunning, Paused: true},
+			want: ErrGamePaused,
+		},
+		{
+			name: "generation in progress returns turn already closed",
+			rec:  RuntimeRecord{Status: RuntimeStatusGenerationInProgress},
+			want: ErrTurnAlreadyClosed,
+		},
+		{
+			name: "generation failed returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusGenerationFailed},
+			want: ErrGamePaused,
+		},
+		{
+			name: "engine unreachable returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusEngineUnreachable},
+			want: ErrGamePaused,
+		},
+		{
+			name: "stopped returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusStopped},
+			want: ErrGamePaused,
+		},
+		{
+			name: "finished returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusFinished},
+			want: ErrGamePaused,
+		},
+		{
+			name: "removed returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusRemoved},
+			want: ErrGamePaused,
+		},
+		{
+			name: "starting returns game paused",
+			rec:  RuntimeRecord{Status: RuntimeStatusStarting},
+			want: ErrGamePaused,
+		},
+		{
+			name: "paused takes precedence over generation in progress",
+			rec:  RuntimeRecord{Status: RuntimeStatusGenerationInProgress, Paused: true},
+			want: ErrGamePaused,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			got := OrdersAcceptStatus(tt.rec)
+			if !errors.Is(got, tt.want) {
+				t.Errorf("OrdersAcceptStatus = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

backend/internal/runtime/scheduler.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"galaxy/backend/internal/dockerclient"
+	"galaxy/backend/internal/engineclient"
 	"galaxy/cronutil"
 
 	"github.com/google/uuid"
@@ -213,6 +214,22 @@ func (sch *Scheduler) loop(ctx context.Context, rec RuntimeRecord, done chan str
 
 // tick runs one engine /admin/turn call under the per-game mutex,
 // publishes the resulting snapshot, and clears `skip_next_tick`.
+//
+// Phase 25 wraps the engine call between two runtime-status flips so
+// the backend order handler can reject late submits while the engine
+// is producing:
+//
+//   - before `Engine.Turn`: runtime status moves to
+//     `generation_in_progress`; the loop's running-only guard tolerates
+//     this because the flip back happens inside the same tick.
+//   - on success: runtime status moves back to `running` (unless the
+//     engine reports `finished`, in which case `publishSnapshot` has
+//     already promoted the row to `finished`).
+//   - on error: runtime status moves to `generation_failed` (engine
+//     validation failure) or `engine_unreachable` (transport / 5xx).
+//     The matching snapshot is forwarded to lobby through
+//     `publishFailureSnapshot` so lobby can flip the game to `paused`
+//     and emit `game.paused`.
 func (sch *Scheduler) tick(ctx context.Context, rec RuntimeRecord) error {
 	mu := sch.svc.gameLock(rec.GameID)
 	if !mu.TryLock() {
@@ -224,10 +241,24 @@ func (sch *Scheduler) tick(ctx context.Context, rec RuntimeRecord) error {
 	if err != nil {
 		return err
 	}
+	if _, err := sch.svc.transitionRuntimeStatus(ctx, rec.GameID, RuntimeStatusGenerationInProgress, ""); err != nil {
+		sch.svc.completeOperation(ctx, op, err)
+		return err
+	}
 	state, err := sch.svc.deps.Engine.Turn(ctx, rec.EngineEndpoint)
 	if err != nil {
 		sch.svc.completeOperation(ctx, op, err)
-		_, _ = sch.svc.transitionRuntimeStatus(ctx, rec.GameID, RuntimeStatusEngineUnreachable, "")
+		failureStatus := RuntimeStatusEngineUnreachable
+		if errors.Is(err, engineclient.ErrEngineValidation) {
+			failureStatus = RuntimeStatusGenerationFailed
+		}
+		_, _ = sch.svc.transitionRuntimeStatus(ctx, rec.GameID, failureStatus, "down")
+		if pubErr := sch.svc.publishFailureSnapshot(ctx, rec.GameID, failureStatus); pubErr != nil {
+			sch.svc.deps.Logger.Warn("publish failure snapshot to lobby",
+				zap.String("game_id", rec.GameID.String()),
+				zap.String("runtime_status", failureStatus),
+				zap.Error(pubErr))
+		}
 		// On engine unreachable, also clear skip_next_tick so the next
 		// real tick can start fresh.
 		_ = sch.clearSkipFlag(ctx, rec.GameID)
@@ -244,6 +275,12 @@ func (sch *Scheduler) tick(ctx context.Context, rec RuntimeRecord) error {
 		sch.svc.completeOperation(ctx, op, err)
 		return err
 	}
+	if !state.Finished {
+		// `publishSnapshot` patches CurrentTurn / EngineHealth but does
+		// not reset the status column; reopen the orders window here so
+		// the next loop iteration finds the runtime back in `running`.
+		_, _ = sch.svc.transitionRuntimeStatus(ctx, rec.GameID, RuntimeStatusRunning, "ok")
+	}
 	sch.svc.completeOperation(ctx, op, nil)
 	_ = sch.clearSkipFlag(ctx, rec.GameID)
 	return nil

backend/internal/runtime/service.go

@@ -257,6 +257,57 @@ func (s *Service) ResolvePlayerMapping(ctx context.Context, gameID, userID uuid.
 	return s.deps.Store.LoadPlayerMapping(ctx, gameID, userID)
 }
 
+// CheckOrdersAccept verifies that the runtime is in a state that
+// accepts user-games commands and orders. It is called by the user
+// game-proxy handlers (`Commands`, `Orders`) before forwarding to
+// engine, so the backend's turn-cutoff and pause guards run before
+// network traffic leaves the host. The decision itself lives in the
+// pure helper `OrdersAcceptStatus` so it can be unit-tested without
+// constructing a full Service.
+//
+// A missing runtime row is surfaced as `ErrNotFound` so the handler
+// keeps its existing 404 behaviour.
+func (s *Service) CheckOrdersAccept(ctx context.Context, gameID uuid.UUID) error {
+	rec, err := s.GetRuntime(ctx, gameID)
+	if err != nil {
+		return err
+	}
+	return OrdersAcceptStatus(rec)
+}
+
+// OrdersAcceptStatus inspects a runtime record and returns the
+// matching sentinel for the user-games order/command pre-check:
+//
+//   - `runtime_status = generation_in_progress` → `ErrTurnAlreadyClosed`.
+//     The cron-driven `Scheduler.tick` has flipped the row before
+//     calling the engine. The order window reopens once the tick
+//     completes successfully.
+//
+//   - `runtime_status ∈ {engine_unreachable, generation_failed,
+//     stopped, finished, removed, starting}` → `ErrGamePaused`.
+//     The game is not in a state that accepts writes; the lobby
+//     state machine has either already flipped the game to
+//     `paused` / `finished` or is still bootstrapping.
+//
+//   - `runtime.Paused = true` → `ErrGamePaused`. The lobby admin
+//     paused the game explicitly.
+//
+//   - `runtime_status = running` and `Paused = false` → nil
+//     (forward).
+func OrdersAcceptStatus(rec RuntimeRecord) error {
+	if rec.Paused {
+		return ErrGamePaused
+	}
+	switch rec.Status {
+	case RuntimeStatusRunning:
+		return nil
+	case RuntimeStatusGenerationInProgress:
+		return ErrTurnAlreadyClosed
+	default:
+		return ErrGamePaused
+	}
+}
+
 // EngineEndpoint returns the engine endpoint URL for gameID. Used by
 // the user game-proxy handlers.
 func (s *Service) EngineEndpoint(ctx context.Context, gameID uuid.UUID) (string, error) {
@@ -812,6 +863,33 @@ func (s *Service) publishSnapshot(ctx context.Context, gameID uuid.UUID, state r
 	return nil
 }
 
+// publishFailureSnapshot forwards a runtime-failure observation to
+// lobby so the game lifecycle can react (e.g. flipping `running` to
+// `paused` on `engine_unreachable` / `generation_failed` per Phase
+// 25). The snapshot carries the unchanged `current_turn` because no
+// new turn has been produced; lobby uses the turn number to anchor
+// the `game.paused` idempotency key.
+//
+// The call is best-effort: lobby errors are returned to the caller
+// (the scheduler tick) so the warn-level logging stays in one place.
+// A missing runtime cache entry (e.g. the row was just removed by
+// the reconciler) collapses into a silent no-op.
+func (s *Service) publishFailureSnapshot(ctx context.Context, gameID uuid.UUID, runtimeStatus string) error {
+	if s.deps.Lobby == nil {
+		return nil
+	}
+	rec, ok := s.deps.Cache.GetRuntime(gameID)
+	if !ok {
+		return nil
+	}
+	return s.deps.Lobby.OnRuntimeSnapshot(ctx, gameID, LobbySnapshot{
+		CurrentTurn:   rec.CurrentTurn,
+		RuntimeStatus: runtimeStatus,
+		EngineHealth:  "down",
+		ObservedAt:    s.deps.Now().UTC(),
+	})
+}
+
 // transitionRuntimeStatus updates the status / engine_health columns
 // and refreshes the cache.
 func (s *Service) transitionRuntimeStatus(ctx context.Context, gameID uuid.UUID, status, health string) (RuntimeRecord, error) {

backend/internal/server/contract_test.go

@@ -45,6 +45,7 @@ var pathParamStubs = map[string]string{
 	"delivery_id": "00000000-0000-0000-0000-000000000006",
 	"user_id": "00000000-0000-0000-0000-000000000007",
 	"device_session_id": "00000000-0000-0000-0000-000000000008",
+	"battle_id": "00000000-0000-0000-0000-000000000009",
 	"id": "1.2.3",
 	"username": "alice",
 	"turn": "42",

backend/internal/server/handlers_user_games.go

@@ -60,6 +60,10 @@ func (h *UserGamesHandlers) Commands() gin.HandlerFunc {
 			return
 		}
 		ctx := c.Request.Context()
+		if err := h.runtime.CheckOrdersAccept(ctx, gameID); err != nil {
+			respondGameProxyError(c, h.logger, "user games commands", ctx, err)
+			return
+		}
 		mapping, err := h.runtime.ResolvePlayerMapping(ctx, gameID, userID)
 		if err != nil {
 			respondGameProxyError(c, h.logger, "user games commands", ctx, err)
@@ -105,6 +109,10 @@ func (h *UserGamesHandlers) Orders() gin.HandlerFunc {
 			return
 		}
 		ctx := c.Request.Context()
+		if err := h.runtime.CheckOrdersAccept(ctx, gameID); err != nil {
+			respondGameProxyError(c, h.logger, "user games orders", ctx, err)
+			return
+		}
 		mapping, err := h.runtime.ResolvePlayerMapping(ctx, gameID, userID)
 		if err != nil {
 			respondGameProxyError(c, h.logger, "user games orders", ctx, err)
@@ -235,6 +243,60 @@ func (h *UserGamesHandlers) Report() gin.HandlerFunc {
 	}
 }
 
+// Battle handles GET /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}.
+// Forwards to the engine's `GET /api/v1/battle/:turn/:uuid`. Path
+// parameters are validated up-front to save a network hop. 404 from
+// the engine is forwarded as 404. The recipient race is resolved
+// from the runtime mapping but not forwarded — engine returns the
+// battle by id, visibility is enforced by the engine state.
+func (h *UserGamesHandlers) Battle() gin.HandlerFunc {
+	if h == nil || h.runtime == nil || h.engine == nil {
+		return handlers.NotImplemented("userGamesBattle")
+	}
+	return func(c *gin.Context) {
+		gameID, ok := parseGameIDParam(c)
+		if !ok {
+			return
+		}
+		turnRaw := c.Param("turn")
+		turn, err := strconv.Atoi(turnRaw)
+		if err != nil || turn < 0 {
+			httperr.Abort(c, http.StatusBadRequest, httperr.CodeInvalidRequest, "turn must be a non-negative integer")
+			return
+		}
+		battleID := c.Param("battle_id")
+		if battleID == "" {
+			httperr.Abort(c, http.StatusBadRequest, httperr.CodeInvalidRequest, "battle id is required")
+			return
+		}
+		userID, ok := userid.FromContext(c.Request.Context())
+		if !ok {
+			httperr.Abort(c, http.StatusBadRequest, httperr.CodeInvalidRequest, "user id missing")
+			return
+		}
+		ctx := c.Request.Context()
+		if _, err := h.runtime.ResolvePlayerMapping(ctx, gameID, userID); err != nil {
+			respondGameProxyError(c, h.logger, "user games battle", ctx, err)
+			return
+		}
+		endpoint, err := h.runtime.EngineEndpoint(ctx, gameID)
+		if err != nil {
+			respondGameProxyError(c, h.logger, "user games battle", ctx, err)
+			return
+		}
+		body, status, err := h.engine.FetchBattle(ctx, endpoint, turn, battleID)
+		if err != nil {
+			respondEngineProxyError(c, h.logger, "user games battle", ctx, body, err)
+			return
+		}
+		if status == http.StatusNotFound {
+			httperr.Abort(c, http.StatusNotFound, httperr.CodeNotFound, "battle not found")
+			return
+		}
+		c.Data(http.StatusOK, "application/json", body)
+	}
+}
+
 // rebindActor decodes a JSON object from raw, sets `actor` to
 // raceName, and re-encodes. Backend never trusts the actor field
 // supplied by the client (per ARCHITECTURE.md §9).
@@ -257,6 +319,12 @@ func respondGameProxyError(c *gin.Context, logger *zap.Logger, op string, ctx co
 	switch {
 	case errors.Is(err, runtime.ErrNotFound):
 		httperr.Abort(c, http.StatusNotFound, httperr.CodeNotFound, "no runtime mapping for this user/game")
+	case errors.Is(err, runtime.ErrTurnAlreadyClosed):
+		httperr.Abort(c, http.StatusConflict, httperr.CodeTurnAlreadyClosed,
+			"turn already closed; orders are not accepted while the engine is producing")
+	case errors.Is(err, runtime.ErrGamePaused):
+		httperr.Abort(c, http.StatusConflict, httperr.CodeGamePaused,
+			"game is paused; orders are not accepted until it resumes")
 	case errors.Is(err, runtime.ErrConflict):
 		httperr.Abort(c, http.StatusConflict, httperr.CodeConflict, err.Error())
 	default:

backend/internal/server/httperr/httperr.go

@@ -23,6 +23,22 @@ const (
 	CodeMethodNotAllowed   = "method_not_allowed"
 	CodeInternalError      = "internal_error"
 	CodeServiceUnavailable = "service_unavailable"
+
+	// CodeTurnAlreadyClosed marks a user-games command or order rejection
+	// caused by the backend's turn-cutoff guard: the request arrived
+	// after the active turn started generating (runtime status
+	// `generation_in_progress` / `generation_failed` / `engine_unreachable`)
+	// and the engine no longer accepts writes for the closing turn. The
+	// caller is expected to wait for the next `game.turn.ready` push and
+	// resubmit against the new turn.
+	CodeTurnAlreadyClosed = "turn_already_closed"
+
+	// CodeGamePaused marks a user-games command or order rejection caused
+	// by the lobby-side game lifecycle: the game is in `paused`,
+	// `finished`, or any other status that does not accept writes. The
+	// caller is expected to wait for the game to resume before
+	// resubmitting.
+	CodeGamePaused = "game_paused"
 )
 
 // Body stores the inner `error` object of the standard envelope.

backend/internal/server/router.go

@@ -263,6 +263,7 @@ func registerUserRoutes(router *gin.Engine, instruments *metrics.Instruments, de
 	userGames.POST("/:game_id/orders", deps.UserGames.Orders())
 	userGames.GET("/:game_id/orders", deps.UserGames.GetOrders())
 	userGames.GET("/:game_id/reports/:turn", deps.UserGames.Report())
+	userGames.GET("/:game_id/battles/:turn/:battle_id", deps.UserGames.Battle())
 
 	userSessions := group.Group("/sessions")
 	userSessions.GET("", deps.UserSessions.List())

backend/openapi.yaml

@@ -1106,6 +1106,44 @@ paths:
           $ref: "#/components/responses/NotImplementedError"
         "500":
           $ref: "#/components/responses/InternalError"
+  /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}:
+    get:
+      tags: [User]
+      operationId: userGamesBattle
+      summary: Read one engine battle report
+      description: |
+        Forwards to the engine's `GET /api/v1/battle/:turn/:uuid`. The
+        engine response body is passed through verbatim. `404 Not Found`
+        is returned when the battle does not exist for the supplied
+        `turn` / `battle_id` pair.
+      security:
+        - UserHeader: []
+      parameters:
+        - $ref: "#/components/parameters/XUserID"
+        - $ref: "#/components/parameters/GameID"
+        - $ref: "#/components/parameters/Turn"
+        - name: battle_id
+          in: path
+          required: true
+          description: Battle identifier (RFC 4122 UUID).
+          schema:
+            type: string
+            format: uuid
+      responses:
+        "200":
+          description: Engine battle report passed through.
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/PassthroughObject"
+        "400":
+          $ref: "#/components/responses/InvalidRequestError"
+        "404":
+          $ref: "#/components/responses/NotFoundError"
+        "501":
+          $ref: "#/components/responses/NotImplementedError"
+        "500":
+          $ref: "#/components/responses/InternalError"
   /api/v1/user/sessions:
     get:
       tags: [User]
@@ -2314,9 +2352,10 @@ components:
           type: string
           description: |
             Stable machine-readable failure marker. The closed set is
-            `not_implemented`, `invalid_request`, `unauthorized`, `not_found`,
-            `conflict`, `method_not_allowed`, `internal_error`,
-            `service_unavailable`.
+            `not_implemented`, `invalid_request`, `unauthorized`,
+            `forbidden`, `not_found`, `conflict`, `method_not_allowed`,
+            `internal_error`, `service_unavailable`,
+            `turn_already_closed`, `game_paused`.
           enum:
             - not_implemented
             - invalid_request
@@ -2327,6 +2366,8 @@ components:
             - method_not_allowed
             - internal_error
             - service_unavailable
+            - turn_already_closed
+            - game_paused
         message:
           type: string
           description: Human-readable client-safe failure description.

docs/ARCHITECTURE.md

@@ -785,9 +785,21 @@ Future scale-out hooks (not in MVP):
 - **runtime snapshot** — engine-status read materialised into the lobby's
   denormalised view: `current_turn`, `runtime_status`,
   `engine_health_summary`, `player_turn_stats`.
-- **turn cutoff** — the `running → generation_in_progress` CAS transition
-  that closes the command window. Commands arriving after the CAS are
-  rejected.
+- **turn cutoff** — the `running → generation_in_progress` runtime-status
+  flip performed by `backend/internal/runtime/scheduler.go` before each
+  engine `/admin/turn` call. Commands and orders arriving while the
+  flag is set are rejected by the user-games handlers with HTTP 409
+  `turn_already_closed`. The matching reopening flip
+  (`generation_in_progress → running`) happens on a successful tick;
+  a failing tick instead drives the lobby to `paused` and fans out
+  `game.paused` (FUNCTIONAL.md §6.3, §6.5).
+- **auto-pause** — the lobby reaction to a failed runtime snapshot
+  (`engine_unreachable` / `generation_failed`): the game flips
+  `running → paused`, the order handlers refuse new submits with
+  HTTP 409 `game_paused`, and `lobby.publishGamePaused` fans out the
+  push event. Only an admin `/resume` followed by a successful tick
+  recovers the game; the UI relies on the next `game.turn.ready` to
+  clear the paused banner.
 - **outbox** — the durable queue of pending mail rows in
   `mail_deliveries`, drained by the mail worker.
 - **freshness window** — the symmetric ±5-minute interval around server

docs/FUNCTIONAL.md

@@ -635,18 +635,40 @@ validity and ordering of in-game decisions. Gateway needs to know
 the typed FB shape only to transcode the wire format; the per-command
 semantics live in the engine.
 
-### 6.3 Turn cutoff
+### 6.3 Turn cutoff and auto-pause
 
 A running game continuously alternates between a command-accepting
-window and a generation phase. The transition `running →
-generation_in_progress` is the cutoff: any command or order that
-arrives after the cutoff is rejected by backend before forwarding,
-because the engine no longer accepts writes for the closing turn.
-After generation finishes, backend re-opens the window for the next
-turn.
+window and a generation phase, driven by the cron expression stored
+in `runtime_records.turn_schedule`. The backend scheduler
+(`backend/internal/runtime/scheduler.go`) wraps each engine
+`/admin/turn` call between two `runtime_status` flips:
+
+- Before the engine call: `running → generation_in_progress`.
+  The user-games command/order handlers
+  (`backend/internal/server/handlers_user_games.go`) consult the
+  per-game runtime record on every request and reject with
+  HTTP 409 + `code = turn_already_closed` while the runtime sits in
+  `generation_in_progress`. The error envelope mirrors backend's
+  standard `httperr` shape: `{"error": {"code":
+  "turn_already_closed", "message": "..."}}`.
+- After a successful tick: `generation_in_progress → running`.
+  The order window re-opens for the new turn and the next
+  scheduled tick continues normally.
+- After a failed tick (`engine_unreachable` /
+  `generation_failed`): the lobby's `OnRuntimeSnapshot` flips the
+  game from `running` to `paused` and publishes a `game.paused`
+  push event (see §6.6). The order handlers reject with HTTP 409
+  + `code = game_paused` until an admin resume succeeds.
 
 `force-next-turn` (admin) schedules a one-shot extra tick that
-advances the next scheduled turn by one cron step.
+advances the next scheduled turn by one cron step; the same
+status-flip and rejection rules apply.
+
+Clients distinguish the two rejections by `code`:
+`turn_already_closed` means "wait for the next `game.turn.ready`
+and resubmit", whereas `game_paused` means "wait for an admin
+resume". The web client implements both reactions in
+`ui/docs/sync-protocol.md`.
 
 ### 6.4 Reports
 
@@ -664,7 +686,69 @@ are exposed in a sticky table of contents (a `<select>` on mobile)
 and the scroll position is preserved across active-view switches
 via SvelteKit's `Snapshot` API.
 
-### 6.5 Side effects
+The Bombings section is a flat read-only table — one row per
+bombing event, columns for `attacker`, `attack_power`, `wiped`
+state and the post-bombing resource snapshot. The Battles section
+is a list of links into the Battle Viewer (see [§6.5](#65-battle-viewer)).
+
+### 6.5 Battle viewer
+
+The Battle Viewer is a dedicated view that replaces the map and
+renders one battle at a time. Entry points:
+
+- A row in the Reports view's Battles section (link with the
+  current turn pinned via `?turn=`).
+- A battle marker on the map (yellow cross drawn through the
+  corners of the square that circumscribes the planet circle;
+  stroke width scales with the protocol length).
+
+The viewer is a logically isolated component that consumes a
+`BattleReport` (shape per `pkg/model/report/battle.go`). The page
+loader (`ui/frontend/src/lib/active-view/battle.svelte`) fetches
+the report through the backend gateway route
+`GET /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}`,
+which forwards verbatim to the engine's
+`GET /api/v1/battle/:turn/:uuid`.
+
+Visual model is radial: the planet sits at the centre, races are
+placed at equal angular spacing on an outer ring, and each race is
+rendered as a cloud of ship-class circles arranged on a Vogel
+sunflower spiral biased toward the planet (the largest group by
+NumberLeft sits closest to the planet, lighter buckets fan behind).
+Tech-variants of the same `(race, className)` collapse into one
+visual bucket labelled `<className>:<numLeft>`; per-class detail
+stays available in the Reports view. Circle radius scales with
+per-ship FullMass (range `[6, 24] px`, per-battle normalisation)
+so heavy ships visually dominate. Observer groups (`inBattle:
+false`) are not drawn. Eliminated races drop out and the survivors
+re-spread on the next frame. The viewer is pinned to the viewport
+(scene grows, log scrolls internally) so no page-level scroll
+appears.
+
+Each frame is one protocol entry; the shot is drawn as a thin line
+from attacker to defender, red on `destroyed`, green otherwise.
+Continuous playback offers 1x / 2x / 4x speeds (400 / 200 / 100 ms
+per frame), plus play/pause, step ±, and rewind. The accessibility
+text protocol below the scene mirrors the same events line-by-line.
+
+Bombings and battles are intentionally not mixed: bombings remain a
+static table in the Reports view; the bombing marker on the map is
+a thin stroke-only ring around the planet (yellow when damaged, red
+when wiped) and a click scrolls the corresponding row into view.
+
+The current report wire carries a `battle: [{ id, planet, shots }]`
+summary per battle so the map markers know where to anchor without
+fetching every full `BattleReport`.
+
+For DEV / e2e the legacy-report CLI
+(`tools/local-dev/legacy-report/cmd/legacy-report-to-json`) emits an
+envelope `{version: 1, report, battles}` where `battles` carries the
+full `BattleReport`-s parsed out of legacy `Battle at (#N)` blocks.
+The synthetic-report loader on the lobby unwraps the envelope and
+hands every battle to `registerSyntheticBattle`, so the Battle Viewer
+resolves any UUID without a network fetch.
+
+### 6.6 Side effects
 
 A successful turn generation publishes a runtime snapshot into the
 lobby module, which updates the denormalised view (current turn,
@@ -672,15 +756,32 @@ runtime status, per-player stats). The engine's "game finished"
 report drives the `running → finished` transition ([Section 3.5](#35-cancellation-and-finish))
 and triggers Race Name Directory promotions ([Section 5](#5-race-name-directory)).
 
-The `game.*` notification kinds (`game.started`, `game.turn.ready`,
-`game.generation.failed`, `game.finished`) are reserved in the
-documentation but have **no producer** in the codebase today; the
-notification catalog explicitly omits them (`backend/internal/notification/catalog.go`).
-Adding a producer is purely additive: register the kind in the
-catalog, populate `MailTemplateID` if email fan-out is desired, and
-have the appropriate domain module call `notification.Submit`.
+Among the `game.*` notification kinds, `game.turn.ready` and
+`game.paused` are wired:
 
-### 6.6 Cross-references
+- `game.turn.ready` —
+  `lobby.Service.OnRuntimeSnapshot` (`backend/internal/lobby/runtime_hooks.go`)
+  emits one intent per advancing `current_turn`, addressed to every
+  active membership of the game, with idempotency key
+  `turn-ready:<game_id>:<turn>` and JSON payload `{game_id, turn}`.
+- `game.paused` — the same hook publishes one intent per transition
+  into `paused` driven by an `engine_unreachable` /
+  `generation_failed` runtime snapshot, addressed to every active
+  membership, with idempotency key `paused:<game_id>:<turn>` and
+  JSON payload `{game_id, turn, reason}`. The runtime status that
+  triggered the transition is carried as `reason` so the UI can
+  differentiate the copy in a future revision.
+
+Both kinds route through the push channel only; email is
+deliberately omitted to avoid per-turn / per-pause spam.
+
+The remaining `game.*` kinds (`game.started`, `game.generation.failed`,
+`game.finished`) and `mail.dead_lettered` are reserved without a
+producer; adding one is purely additive (register the kind in the
+catalog, extend the migration `CHECK` constraint, and call
+`notification.Submit` from the appropriate domain module).
+
+### 6.7 Cross-references
 
 - Backend ↔ engine wire contract (`pkg/model/{order,report,rest}`):
   [ARCHITECTURE.md §9](ARCHITECTURE.md#9-backend--game-engine-communication).

docs/FUNCTIONAL_ru.md

@@ -653,17 +653,40 @@ Backend не парсит содержимое payload команд или пр
 FB-форму только чтобы транскодировать wire-формат; per-command-
 семантика живёт в движке.
 
-### 6.3 Окно хода
+### 6.3 Окно хода и auto-pause
 
 Запущенная игра постоянно чередуется между окном приёма команд
-и фазой генерации. Переход `running → generation_in_progress` —
-cutoff: любая команда или приказ, пришедшие после cutoff,
-отклоняются backend до форварда, потому что движок больше не
-принимает запись для закрывающегося хода. После окончания
-генерации backend заново открывает окно для следующего хода.
+и фазой генерации, управляемой cron-выражением из
+`runtime_records.turn_schedule`. Backend-планировщик
+(`backend/internal/runtime/scheduler.go`) оборачивает каждый
+engine `/admin/turn` двумя `runtime_status`-флипами:
+
+- Перед engine-вызовом: `running → generation_in_progress`.
+  User-games-handler'ы команд/приказов
+  (`backend/internal/server/handlers_user_games.go`) на каждом
+  запросе сверяются с per-game runtime-записью и отклоняют с
+  HTTP 409 + `code = turn_already_closed`, пока runtime в
+  `generation_in_progress`. Тело ошибки — стандартный
+  `httperr`-конверт: `{"error": {"code": "turn_already_closed",
+  "message": "..."}}`.
+- После успешного тика: `generation_in_progress → running`.
+  Окно приказов открывается на новый ход, следующий тик идёт
+  как обычно.
+- После провалившегося тика (`engine_unreachable` /
+  `generation_failed`): `lobby.OnRuntimeSnapshot` переводит игру
+  `running → paused` и публикует push-эвент `game.paused`
+  (см. §6.6). Order-handler'ы отклоняют запросы с HTTP 409 +
+  `code = game_paused`, пока админ не выполнит resume.
 
 `force-next-turn` (admin) планирует one-shot-доп-тик, который
-сдвигает следующий запланированный ход на один cron-шаг.
+сдвигает следующий запланированный ход на один cron-шаг; те же
+правила status-flip и отклонения применимы.
+
+Клиенты различают два варианта отказа по `code`:
+`turn_already_closed` — «дождись следующего `game.turn.ready` и
+отправь ещё раз», `game_paused` — «дождись resume администратором».
+Web-клиент реализует оба сценария согласно
+`ui/docs/sync-protocol.md`.
 
 ### 6.4 Отчёты
 
@@ -681,7 +704,69 @@ empty-state. Якоря секций отображены в sticky-TOC (на м
 `<select>`); позиция скролла сохраняется при переключении активного
 представления через SvelteKit `Snapshot` API.
 
-### 6.5 Побочные эффекты
+Секция бомбардировок — это плоская read-only-таблица: одна строка на
+событие, колонки `attacker`, `attack_power`, признак `wiped` и
+ресурсный снимок после удара. Секция сражений — список ссылок в
+Battle Viewer (см. [§6.5](#65-battle-viewer)).
+
+### 6.5 Battle viewer
+
+Battle Viewer — отдельное представление, заменяющее карту и
+показывающее одну битву. Входы:
+
+- Строка в секции «сражения» в Reports (ссылка с пиннингом
+  текущего хода через `?turn=`).
+- Battle-marker на карте (жёлтый крест через противоположные углы
+  квадрата, описанного вокруг круга планеты; толщина линий растёт
+  с длиной протокола).
+
+Сам Viewer — логически изолированный компонент, потребляющий
+`BattleReport` в форме `pkg/model/report/battle.go`. Страница-обёртка
+(`ui/frontend/src/lib/active-view/battle.svelte`) забирает отчёт
+через backend-маршрут
+`GET /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}`,
+который проксирует ответ engine-эндпоинта
+`GET /api/v1/battle/:turn/:uuid`.
+
+Визуальная модель — радиальная: планета в центре, расы по внешней
+окружности на равных угловых интервалах, внутри расы — облако
+кружков по классам кораблей, выложенное Vogel-спиралью с биасом к
+планете (самая многочисленная группа по NumberLeft — ближе к
+планете, остальные раскручиваются спиралью позади). Tech-варианты
+одного `(race, className)` схлопываются в один визуальный нод
+`<className>:<numLeft>`; детали по тех-уровням остаются в Reports.
+Радиус кружка масштабируется по FullMass корабля (диапазон
+`[6, 24] px`, нормировка на самую тяжёлую группу в битве), так что
+тяжёлые корабли визуально доминируют. Наблюдатели (`inBattle:
+false`) не рисуются. Выбывшие расы убираются из сцены, оставшиеся
+перераспределяются на следующем кадре. Viewer закреплён по высоте
+viewport-а: сцена растягивается, лог скроллит внутри — никаких
+скроллов на уровне страницы.
+
+Каждый кадр — одна запись протокола; выстрел рисуется тонкой линией
+от атакующего к защитнику, красной при `destroyed`, зелёной иначе.
+Непрерывное воспроизведение: 1x / 2x / 4x (400 / 200 / 100 мс на
+кадр), плюс play/pause, шаг вперёд/назад, rewind. Текстовый протокол
+доступности под сценой дублирует те же события построчно.
+
+Бомбардировки и сражения умышленно не смешиваются: бомбардировки
+остаются статической таблицей в Reports; bombing-marker на карте —
+тонкая окружность вокруг планеты (жёлтая при damaged, красная при
+wiped), клик скроллит соответствующую строку в Reports.
+
+Текущая wire-форма отчёта несёт `battle: [{ id, planet, shots }]`
+на каждую битву, чтобы map-маркеры могли расположиться без
+дополнительного запроса полного `BattleReport`.
+
+Для DEV / e2e легаси-CLI
+(`tools/local-dev/legacy-report/cmd/legacy-report-to-json`) выдаёт
+envelope `{version: 1, report, battles}`, где `battles` несёт полные
+`BattleReport`-ы, распарсенные из `Battle at (#N)`-блоков. Synthetic-
+загрузчик в лобби разбирает envelope и регистрирует каждую битву
+через `registerSyntheticBattle`, так что Battle Viewer открывает
+любой UUID без сетевого запроса.
+
+### 6.6 Побочные эффекты
 
 Успешная генерация хода публикует runtime-snapshot в lobby-модуль,
 который обновляет денормализованное вью (текущий ход, runtime-
@@ -690,16 +775,34 @@ status, per-player-stats). Engine-отчёт "game finished" гонит
 ([Раздел 3.5](#35-отмена-и-завершение)) и триггерит Race Name
 Directory-промоушен ([Раздел 5](#5-реестр-названий-рас)).
 
-`game.*`-виды уведомлений (`game.started`, `game.turn.ready`,
-`game.generation.failed`, `game.finished`) зарезервированы в
-документации, но **не имеют поставщика** в кодовой базе сегодня;
-notification-каталог явно их опускает
-(`backend/internal/notification/catalog.go`). Добавление поставщика
-аддитивно: зарегистрировать вид в каталоге, заполнить
-`MailTemplateID`, если нужен email-веер, и заставить нужный
-доменный модуль вызвать `notification.Submit`.
+Из `game.*`-видов уведомлений подключены `game.turn.ready` и
+`game.paused`:
 
-### 6.6 Перекрёстные ссылки
+- `game.turn.ready` —
+  `lobby.Service.OnRuntimeSnapshot` (`backend/internal/lobby/runtime_hooks.go`)
+  выпускает один intent на каждое увеличение `current_turn`,
+  адресуя его всем активным membership-ам игры, с
+  idempotency-ключом `turn-ready:<game_id>:<turn>` и
+  JSON-payload-ом `{game_id, turn}`.
+- `game.paused` — тот же хук публикует один intent на каждое
+  выставление статуса `paused` по runtime-снапшоту
+  (`engine_unreachable` / `generation_failed`), адресуя его всем
+  активным membership-ам игры, с idempotency-ключом
+  `paused:<game_id>:<turn>` и JSON-payload-ом
+  `{game_id, turn, reason}`. `reason` несёт runtime-статус,
+  спровоцировавший переход, чтобы UI смог в будущем
+  дифференцировать копию.
+
+Оба вида направляются только в push-канал; email-фан-аут
+сознательно опущен, чтобы избежать спама на каждом ходе/паузе.
+
+Остальные `game.*`-виды (`game.started`, `game.generation.failed`,
+`game.finished`) и `mail.dead_lettered` зарезервированы без поставщика;
+добавление поставщика чисто аддитивное (зарегистрировать вид в
+каталоге, расширить `CHECK`-констрейнт миграции и вызвать
+`notification.Submit` из подходящего доменного модуля).
+
+### 6.7 Перекрёстные ссылки
 
 - Backend ↔ engine wire-контракт (`pkg/model/{order,report,rest}`):
   [ARCHITECTURE.md §9](ARCHITECTURE.md#9-backend--game-engine-communication).

game/internal/controller/battle_test.go

@@ -8,6 +8,7 @@ import (
 	"galaxy/calc"
 	"galaxy/game/internal/controller"
 	"galaxy/game/internal/model/game"
+	"galaxy/model/report"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -184,3 +185,89 @@ func TestProduceBattles(t *testing.T) {
 		assert.Zero(t, c.ShipGroup(3).Number)
 	}
 }
+
+// TestTransformBattleAggregatesSameShipClass guards against the
+// engine-side variant of the duplicate-class bug. Several ShipGroups
+// of the same ShipClass.ID can take part in the same battle (arrivals
+// from different planets, tech splits, etc.); they must collapse into
+// a single BattleReportGroup with summed Number and NumberLeft. The
+// pre-fix engine cached the first group's index and silently dropped
+// every subsequent group's initial / survivor counts, which manifested
+// downstream as more Destroyed shots in the protocol than the
+// recorded initial roster could account for.
+func TestTransformBattleAggregatesSameShipClass(t *testing.T) {
+	c, g := newCache()
+
+	assert.NoError(t, g.RaceRelation(Race_0.Name, Race_1.Name, game.RelationWar.String()))
+	assert.NoError(t, g.RaceRelation(Race_1.Name, Race_0.Name, game.RelationWar.String()))
+
+	// Two Race_0 groups of the SAME ship class (Race_0_Gunship) plus
+	// one Race_1 group of Race_1_Gunship — all parked on Planet_0
+	// (owned by Race_0; the Race_1 group lands there via the Unsafe
+	// helper that bypasses the ownership check). Group indices land
+	// at 0, 1, 2 in creation order.
+	assert.NoError(t, c.CreateShips(Race_0_idx, Race_0_Gunship, R0_Planet_0_num, 10))
+	assert.NoError(t, c.CreateShips(Race_0_idx, Race_0_Gunship, R0_Planet_0_num, 10))
+	c.CreateShipsUnsafe_T(Race_1_idx, c.MustShipClass(Race_1_idx, Race_1_Gunship).ID, R0_Planet_0_num, 5)
+
+	// Simulate post-battle survivor counts: Group 0 ended the battle
+	// with 8 ships, Group 1 with 6. The aggregated BattleReportGroup
+	// must report NumberLeft = 8 + 6 = 14 (not just the last cached
+	// group's 6 — that's the regression).
+	c.ShipGroup(0).Number = 8
+	c.ShipGroup(1).Number = 6
+
+	b := &controller.Battle{
+		Planet:         R0_Planet_0_num,
+		ObserverGroups: map[int]bool{0: true, 1: true, 2: true},
+		InitialNumbers: map[int]uint{0: 10, 1: 10, 2: 5},
+		// Protocol must reference every in-battle group at least once
+		// (otherwise TransformBattle won't register it through the
+		// `ship()` path). Two shots from Race_1 against each Race_0
+		// group hits both groupIds.
+		Protocol: []controller.BattleAction{
+			{Attacker: 2, Defender: 0, Destroyed: true},
+			{Attacker: 2, Defender: 1, Destroyed: true},
+		},
+	}
+
+	r := controller.TransformBattle(c, b)
+
+	// Two BattleReportGroup entries total: one merged Race_0_Gunship
+	// (groups 0 + 1) and one Race_1_Gunship. NOT three.
+	if got, want := len(r.Ships), 2; got != want {
+		t.Fatalf("len(r.Ships) = %d, want %d (duplicate ShipClass.ID must merge)", got, want)
+	}
+
+	var gunship0, gunship1 *report.BattleReportGroup
+	for i := range r.Ships {
+		grp := r.Ships[i]
+		switch grp.Race {
+		case Race_0.Name:
+			gunship0 = &grp
+		case Race_1.Name:
+			gunship1 = &grp
+		}
+	}
+	if gunship0 == nil || gunship1 == nil {
+		t.Fatalf("missing race entry: race0=%v race1=%v", gunship0, gunship1)
+	}
+
+	if gunship0.ClassName != Race_0_Gunship {
+		t.Errorf("race0.ClassName = %q, want %q", gunship0.ClassName, Race_0_Gunship)
+	}
+	if gunship0.Number != 20 {
+		t.Errorf("race0.Number = %d, want 20 (10+10)", gunship0.Number)
+	}
+	if gunship0.NumberLeft != 14 {
+		t.Errorf("race0.NumberLeft = %d, want 14 (8+6)", gunship0.NumberLeft)
+	}
+	if !gunship0.InBattle {
+		t.Errorf("race0.InBattle = false, want true (both source groups were in-battle)")
+	}
+
+	if gunship1.Number != 5 || gunship1.NumberLeft != 5 {
+		t.Errorf("race1 = (Number=%d, NumberLeft=%d), want (5, 5)",
+			gunship1.Number, gunship1.NumberLeft)
+	}
+}

game/internal/controller/battle_transform.go

@@ -18,10 +18,35 @@ func TransformBattle(c *Cache, b *Battle) *report.BattleReport {
 
 	cacheShipClass := make(map[uuid.UUID]int)
 	cacheRaceName := make(map[uuid.UUID]int)
+	processedGroup := make(map[int]bool)
 
 	addShipGroup := func(groupId int, inBattle bool) int {
 		shipClass := c.ShipGroupShipClass(groupId)
 		sg := c.ShipGroup(groupId)
+		// Several ship-groups of the same race/class can take part
+		// in the same battle (different tech upgrades, arrivals from
+		// different planets, …). They share a single
+		// BattleReportGroup entry keyed by ShipClass.ID — when a
+		// later group lands on a cached class we add its Number and
+		// NumberLeft into the existing entry instead of dropping
+		// them, so the protocol's per-class destroy counts reconcile
+		// with the recorded totals. `processedGroup` guards against
+		// double-counting a single groupId across multiple shots in
+		// the protocol — `ship()` runs on every attacker and defender
+		// reference, the merge must happen once per groupId.
+		if existing, ok := cacheShipClass[shipClass.ID]; ok {
+			if !processedGroup[groupId] {
+				bg := r.Ships[existing]
+				bg.Number += b.InitialNumbers[groupId]
+				bg.NumberLeft += sg.Number
+				if inBattle {
+					bg.InBattle = true
+				}
+				r.Ships[existing] = bg
+				processedGroup[groupId] = true
+			}
+			return existing
+		}
 		itemNumber := len(r.Ships)
 		bg := &report.BattleReportGroup{
 			Race:         c.g.Race[c.RaceIndex(sg.OwnerID)].Name,
@@ -31,22 +56,19 @@ func TransformBattle(c *Cache, b *Battle) *report.BattleReport {
 			ClassName:    shipClass.Name,
 			LoadType:     sg.CargoString(),
 			LoadQuantity: report.F(sg.Load.F()),
+			Tech:         make(map[string]report.Float, len(sg.Tech)),
 		}
 		for t, v := range sg.Tech {
 			bg.Tech[t.String()] = report.F(v.F())
 		}
 		r.Ships[itemNumber] = *bg
 		cacheShipClass[shipClass.ID] = itemNumber
+		processedGroup[groupId] = true
 		return itemNumber
 	}
 
 	ship := func(groupId int) int {
-		shipClass := c.ShipGroupShipClass(groupId)
-		if v, ok := cacheShipClass[shipClass.ID]; ok {
-			return v
-		} else {
-			return addShipGroup(groupId, true)
-		}
+		return addShipGroup(groupId, true)
 	}
 
 	race := func(groupId int) int {

game/internal/controller/controller.go

@@ -38,6 +38,10 @@ type Repo interface {
 	// SaveBattle stores a new battle protocol and battle meta data for turn t
 	SaveBattle(uint, *report.BattleReport, *game.BattleMeta) error
 
+	// LoadBattle reads battle's protocol for turn t and battle id.
+	// Returns false if battle with such id was never stored at turn t
+	LoadBattle(t uint, id uuid.UUID) (*report.BattleReport, bool, error)
+
 	// SaveBombing stores all prodused bombings for turn t
 	SaveBombings(uint, []*game.Bombing) error
 
@@ -143,6 +147,14 @@ func FetchOrder(configure func(*Param), actor string, turn uint) (order *order.U
 	return ec.fetchOrder(actor, turn)
 }
 
+func FetchBattle(configure func(*Param), turn uint, ID uuid.UUID) (b *report.BattleReport, exists bool, err error) {
+	ec, err := NewRepoController(configure)
+	if err != nil {
+		return nil, false, err
+	}
+	return ec.fetchBattle(turn, ID)
+}
+
 func BanishRace(configure func(*Param), actor string) error {
 	ec, err := NewRepoController(configure)
 	if err != nil {
@@ -261,6 +273,14 @@ func (ec *RepoController) fetchOrder(actor string, turn uint) (order *order.User
 	return
 }
 
+func (ec *RepoController) fetchBattle(turn uint, ID uuid.UUID) (order *report.BattleReport, exists bool, err error) {
+	err = ec.executeSafe(func(t uint, c *Controller) error {
+		order, exists, err = ec.Repo.LoadBattle(turn, ID)
+		return err
+	})
+	return
+}
+
 func (ec *RepoController) loadReport(actor string, turn uint) (r *report.Report, err error) {
 	execErr := ec.executeSafe(func(t uint, c *Controller) (exErr error) {
 		id, exErr := c.RaceID(actor)

game/internal/controller/report.go

@@ -37,7 +37,7 @@ func (c *Cache) InitReport(t uint) *mr.Report {
 		OtherScience:           make([]mr.OtherScience, 0, 10),
 		LocalShipClass:         make([]mr.ShipClass, 0, 20),
 		OtherShipClass:         make([]mr.OthersShipClass, 0, 50),
-		Battle:                 make([]uuid.UUID, 0, 10),
+		Battle:                 make([]mr.BattleSummary, 0, 10),
 		Bombing:                make([]*mr.Bombing, 0, 10),
 		IncomingGroup:          make([]mr.IncomingGroup, 0, 10),
 		OnPlanetGroupCache:     make(map[uint][]int),
@@ -342,7 +342,11 @@ func (c *Cache) ReportBattle(ri int, rep *mr.Report, br []*mr.BattleReport) {
 		}
 
 		sliceIndexValidate(&rep.Battle, i)
-		rep.Battle[i] = br[bi].ID
+		rep.Battle[i] = mr.BattleSummary{
+			ID:     br[bi].ID,
+			Planet: br[bi].Planet,
+			Shots:  uint(len(br[bi].Protocol)),
+		}
 		i++
 	}
 }

game/internal/repo/game.go

@@ -13,6 +13,7 @@ package repo
 import (
 	"encoding/json"
 	"fmt"
+	"slices"
 
 	"galaxy/model/order"
 	"galaxy/model/report"
@@ -117,9 +118,25 @@ func loadMeta(s Storage) (*game.GameMeta, error) {
 	return result, nil
 }
 
-func saveMeta(s Storage, t uint, gm *game.GameMeta) error {
+func loadTurnMeta(s Storage, turn uint) (*game.GameMeta, error) {
+	var result *game.GameMeta = new(game.GameMeta)
+	path := fmt.Sprintf("%s/%s", TurnDir(turn), metaPath)
+	exist, err := s.Exists(path)
+	if err != nil {
+		return nil, NewStorageError(err)
+	}
+	if !exist {
+		return result, nil
+	}
+	if err := s.ReadSafe(path, result); err != nil {
+		return nil, NewStorageError(err)
+	}
+	return result, nil
+}
+
+func saveMeta(s Storage, turn uint, gm *game.GameMeta) error {
 	// save turn's meta
-	path := fmt.Sprintf("%s/%s", TurnDir(t), metaPath)
+	path := fmt.Sprintf("%s/%s", TurnDir(turn), metaPath)
 	if err := s.Write(path, gm); err != nil {
 		return NewStorageError(err)
 	}
@@ -131,27 +148,43 @@ func saveMeta(s Storage, t uint, gm *game.GameMeta) error {
 	return nil
 }
 
-func (r *repo) SaveBattle(t uint, b *report.BattleReport, m *game.BattleMeta) error {
+func (r *repo) LoadBattle(turn uint, id uuid.UUID) (*report.BattleReport, bool, error) {
+	meta, err := loadTurnMeta(r.s, turn)
+	if err != nil {
+		return nil, false, err
+	}
+	i := slices.IndexFunc(meta.Battles, func(m game.BattleMeta) bool { return m.BattleID == id })
+	if i < 0 {
+		return nil, false, nil
+	}
+	result, err := loadBattle(r.s, turn, meta.Battles[i].BattleID)
+	if err != nil {
+		return nil, false, err
+	}
+	return result, true, nil
+}
+
+func (r *repo) SaveBattle(turn uint, b *report.BattleReport, m *game.BattleMeta) error {
 	meta, err := loadMeta(r.s)
 	if err != nil {
 		return err
 	}
-	err = saveBattle(r.s, t, b)
+	err = saveBattle(r.s, turn, b)
 	if err != nil {
 		return err
 	}
 	meta.Battles = append(meta.Battles, *m)
-	return saveMeta(r.s, t, meta)
+	return saveMeta(r.s, turn, meta)
 }
 
-func saveBattle(s Storage, t uint, b *report.BattleReport) error {
-	path := fmt.Sprintf("%s/battle/%s.json", TurnDir(t), b.ID.String())
+func saveBattle(s Storage, turn uint, b *report.BattleReport) error {
+	path := fmt.Sprintf("%s/battle/%s.json", TurnDir(turn), b.ID.String())
 	exist, err := s.Exists(path)
 	if err != nil {
 		return NewStorageError(err)
 	}
 	if exist {
-		return NewStateError(fmt.Sprintf("battle %v for turn %d already has been saved", b.ID, t))
+		return NewStateError(fmt.Sprintf("battle %v for turn %d already has been saved", b.ID, turn))
 	}
 	if err := s.Write(path, b); err != nil {
 		return NewStorageError(err)
@@ -159,7 +192,23 @@ func saveBattle(s Storage, t uint, b *report.BattleReport) error {
 	return nil
 }
 
-func (r *repo) SaveBombings(t uint, b []*game.Bombing) error {
+func loadBattle(s Storage, turn uint, id uuid.UUID) (*report.BattleReport, error) {
+	path := fmt.Sprintf("%s/battle/%s.json", TurnDir(turn), id.String())
+	exist, err := s.Exists(path)
+	if err != nil {
+		return nil, NewStorageError(err)
+	}
+	if !exist {
+		return nil, NewStateError(fmt.Sprintf("battle %v for turn %d never was saved", id, turn))
+	}
+	result := new(report.BattleReport)
+	if err := s.ReadSafe(path, result); err != nil {
+		return nil, NewStorageError(err)
+	}
+	return result, nil
+}
+
+func (r *repo) SaveBombings(turn uint, b []*game.Bombing) error {
 	meta, err := loadMeta(r.s)
 	if err != nil {
 		return err
@@ -167,11 +216,11 @@ func (r *repo) SaveBombings(t uint, b []*game.Bombing) error {
 	for i := range b {
 		meta.Bombings = append(meta.Bombings, *b[i])
 	}
-	return saveMeta(r.s, t, meta)
+	return saveMeta(r.s, turn, meta)
 }
 
-func (r *repo) SaveReport(t uint, rep *report.Report) error {
-	return saveReport(r.s, t, rep)
+func (r *repo) SaveReport(turn uint, rep *report.Report) error {
+	return saveReport(r.s, turn, rep)
 }
 
 func saveReport(s Storage, t uint, v *report.Report) error {
@@ -182,12 +231,12 @@ func saveReport(s Storage, t uint, v *report.Report) error {
 	return nil
 }
 
-func (r *repo) LoadReport(t uint, id uuid.UUID) (*report.Report, error) {
-	return loadReport(r.s, t, id)
+func (r *repo) LoadReport(turn uint, id uuid.UUID) (*report.Report, error) {
+	return loadReport(r.s, turn, id)
 }
 
-func loadReport(s Storage, t uint, id uuid.UUID) (*report.Report, error) {
-	path := ReportDir(t, id)
+func loadReport(s Storage, turn uint, id uuid.UUID) (*report.Report, error) {
+	path := ReportDir(turn, id)
 	result := new(report.Report)
 	exist, err := s.Exists(path)
 	if err != nil {

game/internal/router/battle_test.go

@@ -0,0 +1,152 @@
+package router_test
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"galaxy/model/report"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestGetBattleValidation(t *testing.T) {
+	validUUID := uuid.New().String()
+
+	for _, tc := range []struct {
+		description  string
+		turn         string
+		battleID     string
+		expectStatus int
+	}{
+		{"Negative turn", "-1", validUUID, http.StatusBadRequest},
+		{"Non-numeric turn", "abc", validUUID, http.StatusBadRequest},
+		{"Invalid uuid", "0", invalidId, http.StatusBadRequest},
+	} {
+		t.Run(tc.description, func(t *testing.T) {
+			e := &dummyExecutor{}
+			r := setupRouterExecutor(e)
+
+			w := httptest.NewRecorder()
+			path := fmt.Sprintf("/api/v1/battle/%s/%s", tc.turn, tc.battleID)
+			req, _ := http.NewRequest(http.MethodGet, path, nil)
+			r.ServeHTTP(w, req)
+
+			assert.Equal(t, tc.expectStatus, w.Code, w.Body)
+			assert.Equal(t, uuid.Nil, e.FetchBattleID, "FetchBattle must not be called on validation error")
+		})
+	}
+}
+
+func TestGetBattleFound(t *testing.T) {
+	id := uuid.New()
+	raceA := uuid.New()
+	raceB := uuid.New()
+	stored := &report.BattleReport{
+		ID:         id,
+		Planet:     42,
+		PlanetName: "X-Prime",
+		Races: map[int]uuid.UUID{
+			0: raceA,
+			1: raceB,
+		},
+		Ships: map[int]report.BattleReportGroup{
+			10: {
+				Race:         "Alpha",
+				ClassName:    "Drone",
+				Tech:         map[string]report.Float{"WEAPONS": report.F(1)},
+				Number:       5,
+				NumberLeft:   3,
+				LoadType:     "EMP",
+				LoadQuantity: report.F(0),
+				InBattle:     true,
+			},
+			20: {
+				Race:         "Beta",
+				ClassName:    "Spy",
+				Tech:         map[string]report.Float{"SHIELDS": report.F(2)},
+				Number:       4,
+				NumberLeft:   0,
+				LoadType:     "EMP",
+				LoadQuantity: report.F(0),
+				InBattle:     true,
+			},
+		},
+		Protocol: []report.BattleActionReport{
+			{Attacker: 0, AttackerShipClass: 10, Defender: 1, DefenderShipClass: 20, Destroyed: true},
+		},
+	}
+	e := &dummyExecutor{
+		FetchBattleResult: stored,
+		FetchBattleOK:     true,
+	}
+	r := setupRouterExecutor(e)
+
+	w := httptest.NewRecorder()
+	path := fmt.Sprintf("/api/v1/battle/%d/%s", 7, id.String())
+	req, _ := http.NewRequest(http.MethodGet, path, nil)
+	r.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code, w.Body)
+	assert.Equal(t, uint(7), e.FetchBattleTurn)
+	assert.Equal(t, id, e.FetchBattleID)
+
+	var got report.BattleReport
+	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &got))
+	assert.Equal(t, stored.ID, got.ID)
+	assert.Equal(t, stored.Planet, got.Planet)
+	assert.Equal(t, stored.PlanetName, got.PlanetName)
+	assert.Equal(t, stored.Races, got.Races)
+	require.Len(t, got.Ships, len(stored.Ships))
+	assert.Equal(t, stored.Ships[10].ClassName, got.Ships[10].ClassName)
+	assert.Equal(t, stored.Ships[20].NumberLeft, got.Ships[20].NumberLeft)
+	require.Len(t, got.Protocol, 1)
+	assert.Equal(t, stored.Protocol[0], got.Protocol[0])
+}
+
+func TestGetBattleTurnZero(t *testing.T) {
+	id := uuid.New()
+	e := &dummyExecutor{
+		FetchBattleResult: &report.BattleReport{ID: id},
+		FetchBattleOK:     true,
+	}
+	r := setupRouterExecutor(e)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest(http.MethodGet, fmt.Sprintf("/api/v1/battle/0/%s", id.String()), nil)
+	r.ServeHTTP(w, req)
+
+	require.Equal(t, http.StatusOK, w.Code, w.Body)
+	assert.Equal(t, uint(0), e.FetchBattleTurn)
+	assert.Equal(t, id, e.FetchBattleID)
+}
+
+func TestGetBattleNotFound(t *testing.T) {
+	id := uuid.New()
+	e := &dummyExecutor{FetchBattleOK: false}
+	r := setupRouterExecutor(e)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest(http.MethodGet, fmt.Sprintf("/api/v1/battle/3/%s", id.String()), nil)
+	r.ServeHTTP(w, req)
+
+	assert.Equal(t, http.StatusNotFound, w.Code, w.Body)
+	assert.Equal(t, uint(3), e.FetchBattleTurn)
+	assert.Equal(t, id, e.FetchBattleID)
+}
+
+func TestGetBattleEngineError(t *testing.T) {
+	e := &dummyExecutor{FetchBattleErr: errors.New("engine boom")}
+	r := setupRouterExecutor(e)
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest(http.MethodGet, fmt.Sprintf("/api/v1/battle/3/%s", uuid.NewString()), nil)
+	r.ServeHTTP(w, req)
+
+	assert.Equal(t, http.StatusInternalServerError, w.Code, w.Body)
+}

game/internal/router/handler/battle.go

@@ -0,0 +1,37 @@
+package handler
+
+import (
+	"net/http"
+	"strconv"
+
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+)
+
+func BattleHandler(c *gin.Context, executor CommandExecutor) {
+	turn := c.Param("turn")
+	t, err := strconv.Atoi(turn)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	if t < 0 {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "turn number can't be negative"})
+		return
+	}
+	id := c.Param("uuid")
+	battleID, err := uuid.Parse(id)
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+	r, exists, err := executor.FetchBattle(uint(t), battleID)
+	if errorResponse(c, err) {
+		return
+	}
+	if !exists {
+		c.JSON(http.StatusNotFound, gin.H{"error": "unknown battle"})
+		return
+	}
+	c.JSON(http.StatusOK, r)
+}

game/internal/router/handler/handler.go

@@ -17,6 +17,7 @@ import (
 
 	"github.com/gin-gonic/gin"
 	"github.com/go-playground/validator/v10"
+	"github.com/google/uuid"
 )
 
 type CommandExecutor interface {
@@ -29,6 +30,7 @@ type CommandExecutor interface {
 	Execute(cmd ...Command) error
 	ValidateOrder(actor string, cmd ...order.DecodableCommand) (*order.UserGamesOrder, error)
 	FetchOrder(actor string, turn uint) (*order.UserGamesOrder, bool, error)
+	FetchBattle(turn uint, ID uuid.UUID) (*report.BattleReport, bool, error)
 }
 
 type Command func(controller.Ctrl) error
@@ -86,6 +88,10 @@ func (e *executor) FetchOrder(actor string, turn uint) (*order.UserGamesOrder, b
 	return controller.FetchOrder(e.cfg, actor, turn)
 }
 
+func (e *executor) FetchBattle(turn uint, ID uuid.UUID) (*report.BattleReport, bool, error) {
+	return controller.FetchBattle(e.cfg, turn, ID)
+}
+
 func (e *executor) GenerateGame(races []string) (rest.StateResponse, error) {
 	s, err := controller.GenerateGame(e.cfg, races)
 	if err != nil {

game/internal/router/router.go

@@ -76,6 +76,7 @@ func setupRouter(executor handler.CommandExecutor) *gin.Engine {
 	groupV1.GET("/report", func(ctx *gin.Context) { handler.ReportHandler(ctx, executor) })
 	groupV1.PUT("/order", func(ctx *gin.Context) { handler.PutOrderHandler(ctx, executor) })
 	groupV1.GET("/order", func(ctx *gin.Context) { handler.GetOrderHandler(ctx, executor) })
+	groupV1.GET("/battle/:turn/:uuid", func(ctx *gin.Context) { handler.BattleHandler(ctx, executor) })
 
 	// /command is reserved for future use; any API request for orders should use /order
 	groupV1.PUT("/command", LimitMiddleware(1), func(ctx *gin.Context) { handler.CommandHandler(ctx, executor) })

game/internal/router/router_helper_test.go

@@ -45,6 +45,13 @@ type dummyExecutor struct {
 	FetchOrderResult *order.UserGamesOrder
 	FetchOrderOK     bool
 	FetchOrderErr    error
+
+	// FetchBattle controls and observes calls to FetchBattle.
+	FetchBattleTurn   uint
+	FetchBattleID     uuid.UUID
+	FetchBattleResult *report.BattleReport
+	FetchBattleOK     bool
+	FetchBattleErr    error
 }
 
 func (e *dummyExecutor) ValidateOrder(actor string, cmd ...order.DecodableCommand) (*order.UserGamesOrder, error) {
@@ -68,6 +75,12 @@ func (e *dummyExecutor) FetchOrder(actor string, turn uint) (*order.UserGamesOrd
 	return e.FetchOrderResult, e.FetchOrderOK, e.FetchOrderErr
 }
 
+func (e *dummyExecutor) FetchBattle(turn uint, ID uuid.UUID) (*report.BattleReport, bool, error) {
+	e.FetchBattleTurn = turn
+	e.FetchBattleID = ID
+	return e.FetchBattleResult, e.FetchBattleOK, e.FetchBattleErr
+}
+
 func (e *dummyExecutor) Execute(command ...handler.Command) error {
 	e.CommandsExecuted = len(command)
 	return nil

game/openapi.yaml

@@ -207,6 +207,33 @@ paths:
           $ref: "#/components/responses/ValidationError"
         "500":
           $ref: "#/components/responses/InternalError"
+  /api/v1/battle/{turn}/{uuid}:
+    get:
+      tags:
+        - PlayerActions
+      operationId: getBattle
+      summary: Fetch a single battle report
+      description: |
+        Returns the full `BattleReport` for the supplied `turn` and battle
+        identifier. The `turn` segment must be a non-negative integer; the
+        `uuid` segment must be a valid RFC 4122 UUID. Responds with
+        `404 Not Found` when no battle is stored for the supplied pair.
+      parameters:
+        - $ref: "#/components/parameters/BattleTurnParam"
+        - $ref: "#/components/parameters/BattleIDParam"
+      responses:
+        "200":
+          description: Battle report for the supplied turn and identifier.
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/BattleReport"
+        "400":
+          $ref: "#/components/responses/ValidationError"
+        "404":
+          description: No battle exists for the supplied turn and identifier.
+        "500":
+          $ref: "#/components/responses/InternalError"
   /api/v1/admin/turn:
     put:
       tags:
@@ -265,6 +292,22 @@ components:
         type: integer
         minimum: 0
         default: 0
+    BattleTurnParam:
+      name: turn
+      in: path
+      required: true
+      description: Turn number the battle was generated on.
+      schema:
+        type: integer
+        minimum: 0
+    BattleIDParam:
+      name: uuid
+      in: path
+      required: true
+      description: Battle identifier (RFC 4122 UUID).
+      schema:
+        type: string
+        format: uuid
   schemas:
     HealthzResponse:
       type: object
@@ -541,10 +584,9 @@ components:
             $ref: "#/components/schemas/OtherShipClass"
         battle:
           type: array
-          description: UUIDs of battle reports relevant to this turn.
+          description: Battle summaries relevant to this turn.
           items:
-            type: string
-            format: uuid
+            $ref: "#/components/schemas/BattleSummary"
         bombing:
           type: array
           description: Bombing events that occurred during this turn.
@@ -788,6 +830,148 @@ components:
         wiped:
           type: boolean
           description: True when all population was eliminated by the bombing.
+    BattleSummary:
+      type: object
+      description: |
+        Identifies one battle relevant to the report recipient. Used by
+        clients to render a battle marker on the map without fetching
+        the full BattleReport. `planet` locates the marker; `shots`
+        scales the marker stroke with the battle length.
+      required:
+        - id
+        - planet
+        - shots
+      properties:
+        id:
+          type: string
+          format: uuid
+          description: Battle identifier; fetch the full report via `/api/v1/battle/{turn}/{uuid}`.
+        planet:
+          type: integer
+          minimum: 0
+          description: Planet number the battle took place on.
+        shots:
+          type: integer
+          minimum: 0
+          description: Number of shots exchanged during the battle.
+    BattleReport:
+      type: object
+      description: |
+        Full battle report. `races` and `ships` are JSON objects whose
+        keys are stringified integers used to cross-reference entries
+        from `protocol`: a `BattleActionReport` carries integer indices
+        into both maps. The serialised key is a string because JSON
+        object keys are always strings.
+      required:
+        - id
+        - planet
+        - planetName
+        - races
+        - ships
+        - protocol
+      properties:
+        id:
+          type: string
+          format: uuid
+          description: Battle identifier.
+        planet:
+          type: integer
+          minimum: 0
+          description: Planet number the battle took place on.
+        planetName:
+          type: string
+          description: Planet name at battle start.
+        races:
+          type: object
+          description: |
+            Participating races keyed by the integer index used in
+            `protocol.a` / `protocol.d`. Values are race identifiers.
+          additionalProperties:
+            type: string
+            format: uuid
+        ships:
+          type: object
+          description: |
+            Participating ship groups keyed by the integer index used
+            in `protocol.sa` / `protocol.sd`.
+          additionalProperties:
+            $ref: "#/components/schemas/BattleReportGroup"
+        protocol:
+          type: array
+          description: Ordered list of shots exchanged during the battle.
+          items:
+            $ref: "#/components/schemas/BattleActionReport"
+    BattleReportGroup:
+      type: object
+      description: One ship group participating in the battle.
+      required:
+        - race
+        - className
+        - tech
+        - num
+        - numLeft
+        - loadType
+        - loadQuantity
+        - inBattle
+      properties:
+        race:
+          type: string
+          description: Race name of the group owner.
+        className:
+          type: string
+          description: Ship class name; resolvable through `LocalShipClass` or `OtherShipClass`.
+        tech:
+          type: object
+          description: Technology levels keyed by tech type name.
+          additionalProperties:
+            type: number
+        num:
+          type: integer
+          minimum: 0
+          description: Initial number of ships in this group.
+        numLeft:
+          type: integer
+          minimum: 0
+          description: Number of ships remaining at the end of the battle.
+        loadType:
+          type: string
+          description: Type of cargo loaded.
+        loadQuantity:
+          type: number
+          description: Quantity of cargo loaded.
+        inBattle:
+          type: boolean
+          description: |
+            True when the group actually fights. False groups observe
+            the battle in peace state and never fire or take damage.
+    BattleActionReport:
+      type: object
+      description: |
+        One shot in the battle. Attacker and defender indices reference
+        `BattleReport.races`; ship-class indices reference
+        `BattleReport.ships`.
+      required:
+        - a
+        - sa
+        - d
+        - sd
+        - x
+      properties:
+        a:
+          type: integer
+          description: Index into `BattleReport.races` for the attacker.
+        sa:
+          type: integer
+          description: Index into `BattleReport.ships` for the attacker's group.
+        d:
+          type: integer
+          description: Index into `BattleReport.races` for the defender.
+        sd:
+          type: integer
+          description: Index into `BattleReport.ships` for the defender's group.
+        x:
+          type: boolean
+          description: True when the defender ship was destroyed by this shot.
     IncomingGroup:
       type: object
       description: An identified ship group inbound toward a planet of this race.

game/openapi_contract_test.go

@@ -79,6 +79,13 @@ func TestGameOpenAPISpecFreezesResponseSchemas(t *testing.T) {
 			status:  http.StatusOK,
 			wantRef: "#/components/schemas/HealthzResponse",
 		},
+		{
+			name:    "get battle",
+			path:    "/api/v1/battle/{turn}/{uuid}",
+			method:  http.MethodGet,
+			status:  http.StatusOK,
+			wantRef: "#/components/schemas/BattleReport",
+		},
 	}
 
 	for _, tt := range tests {
@@ -271,6 +278,71 @@ func TestGameOpenAPISpecFreezesCommandRequest(t *testing.T) {
 	require.Equal(t, uint64(1), cmdSchema.Value.MinItems, "CommandRequest.cmd minItems must be 1")
 }
 
+func TestGameOpenAPISpecFreezesGetBattleOperation(t *testing.T) {
+	t.Parallel()
+
+	doc := loadOpenAPISpec(t)
+	operation := getOpenAPIOperation(t, doc, "/api/v1/battle/{turn}/{uuid}", http.MethodGet)
+
+	require.Equal(t, "getBattle", operation.OperationID, "GET /api/v1/battle/{turn}/{uuid} operation id")
+
+	paramRefs := make(map[string]bool)
+	for _, p := range operation.Parameters {
+		require.NotNil(t, p.Value, "parameter must have value")
+		paramRefs[p.Ref] = true
+	}
+	require.True(t, paramRefs["#/components/parameters/BattleTurnParam"], "GET /api/v1/battle/{turn}/{uuid} must reference BattleTurnParam")
+	require.True(t, paramRefs["#/components/parameters/BattleIDParam"], "GET /api/v1/battle/{turn}/{uuid} must reference BattleIDParam")
+
+	require.NotNil(t, operation.Responses, "operation must declare responses")
+	notFound := operation.Responses.Status(http.StatusNotFound)
+	require.NotNil(t, notFound, "operation must declare 404 response")
+	require.NotNil(t, notFound.Value, "404 response must have a value")
+}
+
+func TestGameOpenAPISpecFreezesBattleReport(t *testing.T) {
+	t.Parallel()
+
+	doc := loadOpenAPISpec(t)
+
+	reportSchema := componentSchemaRef(t, doc, "BattleReport")
+	assertRequiredFields(t, reportSchema, "id", "planet", "planetName", "races", "ships", "protocol")
+
+	groupSchema := componentSchemaRef(t, doc, "BattleReportGroup")
+	assertRequiredFields(t, groupSchema, "race", "className", "tech", "num", "numLeft", "loadType", "loadQuantity", "inBattle")
+
+	actionSchema := componentSchemaRef(t, doc, "BattleActionReport")
+	assertRequiredFields(t, actionSchema, "a", "sa", "d", "sd", "x")
+
+	protocolSchema := reportSchema.Value.Properties["protocol"]
+	require.NotNil(t, protocolSchema, "BattleReport.protocol schema must exist")
+	require.True(t, protocolSchema.Value.Type.Is("array"), "BattleReport.protocol must be array")
+	require.NotNil(t, protocolSchema.Value.Items, "BattleReport.protocol items must be defined")
+	assertSchemaRef(t, protocolSchema.Value.Items, "#/components/schemas/BattleActionReport", "BattleReport.protocol items schema")
+
+	shipsSchema := reportSchema.Value.Properties["ships"]
+	require.NotNil(t, shipsSchema, "BattleReport.ships schema must exist")
+	require.True(t, shipsSchema.Value.Type.Is("object"), "BattleReport.ships must be object")
+	require.NotNil(t, shipsSchema.Value.AdditionalProperties.Schema, "BattleReport.ships additionalProperties must be a schema")
+	assertSchemaRef(t, shipsSchema.Value.AdditionalProperties.Schema, "#/components/schemas/BattleReportGroup", "BattleReport.ships additionalProperties schema")
+}
+
+func TestGameOpenAPISpecFreezesBattleSummary(t *testing.T) {
+	t.Parallel()
+
+	doc := loadOpenAPISpec(t)
+
+	summary := componentSchemaRef(t, doc, "BattleSummary")
+	assertRequiredFields(t, summary, "id", "planet", "shots")
+
+	report := componentSchemaRef(t, doc, "Report")
+	battle := report.Value.Properties["battle"]
+	require.NotNil(t, battle, "Report.battle schema must exist")
+	require.True(t, battle.Value.Type.Is("array"), "Report.battle must be array")
+	require.NotNil(t, battle.Value.Items, "Report.battle items must be defined")
+	assertSchemaRef(t, battle.Value.Items, "#/components/schemas/BattleSummary", "Report.battle items schema")
+}
+
 func TestGameOpenAPISpecHealthzStatusEnum(t *testing.T) {
 	t.Parallel()
 

gateway/README.md

@@ -385,6 +385,12 @@ The current direct `Gateway -> User` self-service boundary uses that pattern:
 - business error projection:
   - gateway `result_code`
   - FlatBuffers error payload mirroring User Service `code` and `message`
+  - User Service `code` values pass through verbatim as `result_code`
+    via `projectUserBackendError`; known non-`ok` codes that clients
+    branch on include `turn_already_closed` (Phase 25 turn cutoff,
+    HTTP 409 from `Orders` / `Commands` while the runtime is in
+    `generation_in_progress`) and `game_paused` (Phase 25 auto-pause,
+    HTTP 409 while the game is in `paused` / `finished` / `removed`).
 
 The request envelope version literal is `v1`.
 `payload_hash` is the raw 32-byte SHA-256 digest of `payload_bytes`.

pkg/model/report/battle.go

@@ -6,32 +6,64 @@ import (
 	"github.com/google/uuid"
 )
 
+// BattleSummary identifies one battle relevant to the report recipient
+// and carries the data needed to render a battle marker on the map
+// without fetching the full BattleReport. Planet locates the marker;
+// Shots scales the marker stroke with the battle length.
+type BattleSummary struct {
+	ID     uuid.UUID `json:"id"`
+	Planet uint      `json:"planet"`
+	Shots  uint      `json:"shots"`
+}
+
 type BattleReport struct {
-	ID         uuid.UUID                 `json:"id"`
-	Planet     uint                      `json:"planet"`
-	PlanetName string                    `json:"planetName"`
-	Races      map[int]uuid.UUID         `json:"races"`
-	Ships      map[int]BattleReportGroup `json:"ships"`
-	Protocol   []BattleActionReport      `json:"protocol"`
+	// Battle unique ID
+	ID uuid.UUID `json:"id"`
+	// Planet number
+	Planet uint `json:"planet"`
+	// Planet name at battle start
+	PlanetName string `json:"planetName"`
+	// Races participating map: <key:RaceID>
+	Races map[int]uuid.UUID `json:"races"`
+	// Ships Groups participating map: <key:BattleReportGroup>
+	Ships map[int]BattleReportGroup `json:"ships"`
+	// Battle's firing protocol
+	Protocol []BattleActionReport `json:"protocol"`
 }
 
 type BattleReportGroup struct {
-	InBattle     bool             `json:"inBattle"`
-	Number       uint             `json:"num"`
-	NumberLeft   uint             `json:"numLeft"`
-	LoadQuantity Float            `json:"loadQuantity"`
-	Tech         map[string]Float `json:"tech"`
-	Race         string           `json:"race"`
-	ClassName    string           `json:"className"`
-	LoadType     string           `json:"loadType"`
+	// Name of the race
+	Race string `json:"race"`
+	// Name of the Ship Class.
+	// By design, ship's info MUST be present in Game's Repors in 'LocalShipClass' or 'OtherShipClass'
+	ClassName string `json:"className"`
+	// Ship Group's technologies mapping <tech:level>
+	Tech map[string]Float `json:"tech"`
+	// Initial number of ships in this group
+	Number uint `json:"num"`
+	// Number of ships left after battle
+	NumberLeft uint `json:"numLeft"`
+	// Type of cargo loaded
+	LoadType string `json:"loadType"`
+	// Quantity of cargo loaded
+	LoadQuantity Float `json:"loadQuantity"`
+	// A Race with its ships can be in Peace state with all participants,
+	// so no shots will be fired and no damage taken, participating only as viewer
+	// when InBattle=false
+	InBattle bool `json:"inBattle"`
 }
 
 type BattleActionReport struct {
-	Attacker          int  `json:"a"`
-	AttackerShipClass int  `json:"sa"`
-	Defender          int  `json:"d"`
-	DefenderShipClass int  `json:"sd"`
-	Destroyed         bool `json:"x"`
+	// `key` from BattleReport.Races map
+	Attacker int `json:"a"`
+	// `key` from BattleReport.Ships map
+	AttackerShipClass int `json:"sa"`
+	// `key` from BattleReport.Races map
+	Defender int `json:"d"`
+	// `key` from BattleReport.Ships map
+	DefenderShipClass int `json:"sd"`
+	// Was ship destroyed after attack or survived under shields
+	Destroyed bool `json:"x"`
 }
 
 func (b BattleReport) MarshalBinary() (data []byte, err error) {

pkg/model/report/report.go

@@ -33,7 +33,7 @@ type Report struct {
 	OtherScience       []OtherScience       `json:"otherScience,omitempty"`
 	LocalShipClass     []ShipClass          `json:"localShipClass,omitempty"`
 	OtherShipClass     []OthersShipClass    `json:"otherShipClass,omitempty"`
-	Battle             []uuid.UUID          `json:"battle,omitempty"`
+	Battle             []BattleSummary      `json:"battle,omitempty"`
 	Bombing            []*Bombing           `json:"bombing,omitempty"`
 	IncomingGroup      []IncomingGroup      `json:"incomingGroup,omitempty"`
 	LocalPlanet        []LocalPlanet        `json:"localPlanet,omitempty"`

pkg/schema/fbs/report.fbs

@@ -196,6 +196,17 @@ table LocalFleet {
   state:string;
 }
 
+// BattleSummary identifies one battle the report recipient
+// participated in or could see on a planet. `planet` lets the map
+// place a battle marker without fetching the full BattleReport;
+// `shots` lets the marker scale its stroke with the protocol length
+// (1 shot → thinnest cross, 100+ shots → maximum cross thickness).
+table BattleSummary {
+  id:common.UUID (required);
+  planet:uint64;
+  shots:uint64;
+}
+
 table Report {
   version:uint64;
   turn:uint64;
@@ -210,7 +221,7 @@ table Report {
   other_science:[OtherScience];
   local_ship_class:[ShipClass];
   other_ship_class:[OthersShipClass];
-  battle:[common.UUID];
+  battle:[BattleSummary];
   bombing:[Bombing];
   incoming_group:[IncomingGroup];
   local_planet:[LocalPlanet];

pkg/schema/fbs/report/BattleSummary.go

@@ -0,0 +1,97 @@
+// Code generated by the FlatBuffers compiler. DO NOT EDIT.
+
+package report
+
+import (
+	flatbuffers "github.com/google/flatbuffers/go"
+
+	common "galaxy/schema/fbs/common"
+)
+
+type BattleSummary struct {
+	_tab flatbuffers.Table
+}
+
+func GetRootAsBattleSummary(buf []byte, offset flatbuffers.UOffsetT) *BattleSummary {
+	n := flatbuffers.GetUOffsetT(buf[offset:])
+	x := &BattleSummary{}
+	x.Init(buf, n+offset)
+	return x
+}
+
+func FinishBattleSummaryBuffer(builder *flatbuffers.Builder, offset flatbuffers.UOffsetT) {
+	builder.Finish(offset)
+}
+
+func GetSizePrefixedRootAsBattleSummary(buf []byte, offset flatbuffers.UOffsetT) *BattleSummary {
+	n := flatbuffers.GetUOffsetT(buf[offset+flatbuffers.SizeUint32:])
+	x := &BattleSummary{}
+	x.Init(buf, n+offset+flatbuffers.SizeUint32)
+	return x
+}
+
+func FinishSizePrefixedBattleSummaryBuffer(builder *flatbuffers.Builder, offset flatbuffers.UOffsetT) {
+	builder.FinishSizePrefixed(offset)
+}
+
+func (rcv *BattleSummary) Init(buf []byte, i flatbuffers.UOffsetT) {
+	rcv._tab.Bytes = buf
+	rcv._tab.Pos = i
+}
+
+func (rcv *BattleSummary) Table() flatbuffers.Table {
+	return rcv._tab
+}
+
+func (rcv *BattleSummary) Id(obj *common.UUID) *common.UUID {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(4))
+	if o != 0 {
+		x := o + rcv._tab.Pos
+		if obj == nil {
+			obj = new(common.UUID)
+		}
+		obj.Init(rcv._tab.Bytes, x)
+		return obj
+	}
+	return nil
+}
+
+func (rcv *BattleSummary) Planet() uint64 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		return rcv._tab.GetUint64(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *BattleSummary) MutatePlanet(n uint64) bool {
+	return rcv._tab.MutateUint64Slot(6, n)
+}
+
+func (rcv *BattleSummary) Shots() uint64 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(8))
+	if o != 0 {
+		return rcv._tab.GetUint64(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *BattleSummary) MutateShots(n uint64) bool {
+	return rcv._tab.MutateUint64Slot(8, n)
+}
+
+func BattleSummaryStart(builder *flatbuffers.Builder) {
+	builder.StartObject(3)
+}
+func BattleSummaryAddId(builder *flatbuffers.Builder, id flatbuffers.UOffsetT) {
+	builder.PrependStructSlot(0, flatbuffers.UOffsetT(id), 0)
+}
+func BattleSummaryAddPlanet(builder *flatbuffers.Builder, planet uint64) {
+	builder.PrependUint64Slot(1, planet, 0)
+}
+func BattleSummaryAddShots(builder *flatbuffers.Builder, shots uint64) {
+	builder.PrependUint64Slot(2, shots, 0)
+}
+func BattleSummaryEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	return builder.EndObject()
+}

pkg/schema/fbs/report/Report.go

@@ -4,8 +4,6 @@ package report
 
 import (
 	flatbuffers "github.com/google/flatbuffers/go"
-
-	common "galaxy/schema/fbs/common"
 )
 
 type Report struct {
@@ -231,11 +229,12 @@ func (rcv *Report) OtherShipClassLength() int {
 	return 0
 }
 
-func (rcv *Report) Battle(obj *common.UUID, j int) bool {
+func (rcv *Report) Battle(obj *BattleSummary, j int) bool {
 	o := flatbuffers.UOffsetT(rcv._tab.Offset(30))
 	if o != 0 {
 		x := rcv._tab.Vector(o)
-		x += flatbuffers.UOffsetT(j) * 16
+		x += flatbuffers.UOffsetT(j) * 4
+		x = rcv._tab.Indirect(x)
 		obj.Init(rcv._tab.Bytes, x)
 		return true
 	}
@@ -551,7 +550,7 @@ func ReportAddBattle(builder *flatbuffers.Builder, battle flatbuffers.UOffsetT)
 	builder.PrependUOffsetTSlot(13, flatbuffers.UOffsetT(battle), 0)
 }
 func ReportStartBattleVector(builder *flatbuffers.Builder, numElems int) flatbuffers.UOffsetT {
-	return builder.StartVector(16, numElems, 8)
+	return builder.StartVector(4, numElems, 4)
 }
 func ReportAddBombing(builder *flatbuffers.Builder, bombing flatbuffers.UOffsetT) {
 	builder.PrependUOffsetTSlot(14, flatbuffers.UOffsetT(bombing), 0)

pkg/transcoder/report.go

@@ -10,7 +10,6 @@ import (
 	fbs "galaxy/schema/fbs/report"
 
 	flatbuffers "github.com/google/flatbuffers/go"
-	"github.com/google/uuid"
 )
 
 // ReportToPayload converts model.Report from the internal representation to
@@ -120,7 +119,7 @@ func ReportToPayload(report *model.Report) ([]byte, error) {
 	otherScienceVector := encodeReportOffsetVector(builder, len(otherScienceOffsets), fbs.ReportStartOtherScienceVector, otherScienceOffsets)
 	localShipClassVector := encodeReportOffsetVector(builder, len(localShipClassOffsets), fbs.ReportStartLocalShipClassVector, localShipClassOffsets)
 	otherShipClassVector := encodeReportOffsetVector(builder, len(otherShipClassOffsets), fbs.ReportStartOtherShipClassVector, otherShipClassOffsets)
-	battleVector := encodeReportUUIDVector(builder, report.Battle)
+	battleVector := encodeReportBattleSummaries(builder, report.Battle)
 	bombingVector := encodeReportOffsetVector(builder, len(bombingOffsets), fbs.ReportStartBombingVector, bombingOffsets)
 	incomingGroupVector := encodeReportOffsetVector(builder, len(incomingGroupOffsets), fbs.ReportStartIncomingGroupVector, incomingGroupOffsets)
 	localPlanetVector := encodeReportOffsetVector(builder, len(localPlanetOffsets), fbs.ReportStartLocalPlanetVector, localPlanetOffsets)
@@ -734,13 +733,29 @@ func decodeReportBattleVector(flatReport *fbs.Report, result *model.Report) erro
 		return nil
 	}
 
-	result.Battle = make([]uuid.UUID, length)
-	item := new(commonfbs.UUID)
+	result.Battle = make([]model.BattleSummary, length)
+	item := new(fbs.BattleSummary)
+	idHolder := new(commonfbs.UUID)
 	for i := 0; i < length; i++ {
 		if !flatReport.Battle(item, i) {
+			return fmt.Errorf("decode report battle %d: battle is missing", i)
+		}
+		if item.Id(idHolder) == nil {
 			return fmt.Errorf("decode report battle %d: battle id is missing", i)
 		}
-		result.Battle[i] = uuidFromHiLo(item.Hi(), item.Lo())
+		planet, err := uint64ToUint(item.Planet(), "planet")
+		if err != nil {
+			return fmt.Errorf("decode report battle %d: %w", i, err)
+		}
+		shots, err := uint64ToUint(item.Shots(), "shots")
+		if err != nil {
+			return fmt.Errorf("decode report battle %d: %w", i, err)
+		}
+		result.Battle[i] = model.BattleSummary{
+			ID:     uuidFromHiLo(idHolder.Hi(), idHolder.Lo()),
+			Planet: planet,
+			Shots:  shots,
+		}
 	}
 
 	return nil
@@ -1299,17 +1314,26 @@ func encodeReportOffsetVector(
 	return builder.EndVector(length)
 }
 
-func encodeReportUUIDVector(builder *flatbuffers.Builder, ids []uuid.UUID) flatbuffers.UOffsetT {
-	if len(ids) == 0 {
+func encodeReportBattleSummaries(builder *flatbuffers.Builder, summaries []model.BattleSummary) flatbuffers.UOffsetT {
+	if len(summaries) == 0 {
 		return 0
 	}
 
-	fbs.ReportStartBattleVector(builder, len(ids))
-	for i := len(ids) - 1; i >= 0; i-- {
-		hi, lo := uuidToHiLo(ids[i])
-		commonfbs.CreateUUID(builder, hi, lo)
+	offsets := make([]flatbuffers.UOffsetT, len(summaries))
+	for i := range summaries {
+		hi, lo := uuidToHiLo(summaries[i].ID)
+		fbs.BattleSummaryStart(builder)
+		fbs.BattleSummaryAddId(builder, commonfbs.CreateUUID(builder, hi, lo))
+		fbs.BattleSummaryAddPlanet(builder, uint64(summaries[i].Planet))
+		fbs.BattleSummaryAddShots(builder, uint64(summaries[i].Shots))
+		offsets[i] = fbs.BattleSummaryEnd(builder)
 	}
-	return builder.EndVector(len(ids))
+
+	fbs.ReportStartBattleVector(builder, len(offsets))
+	for i := len(offsets) - 1; i >= 0; i-- {
+		builder.PrependUOffsetT(offsets[i])
+	}
+	return builder.EndVector(len(offsets))
 }
 
 func encodeReportRouteEntryVector(builder *flatbuffers.Builder, route map[uint]string) flatbuffers.UOffsetT {

pkg/transcoder/report_test.go

@@ -255,9 +255,17 @@ func sampleReport() *model.Report {
 		OtherShipClass: []model.OthersShipClass{
 			{Race: "Martians", ShipClass: model.ShipClass{Name: "destroyer", Drive: model.Float(1.75), Armament: 6, Weapons: model.Float(2.25), Shields: model.Float(2.75), Cargo: model.Float(3.25), Mass: model.Float(10.5)}},
 		},
-		Battle: []uuid.UUID{
-			uuid.MustParse("11111111-1111-1111-1111-111111111111"),
-			uuid.MustParse("22222222-2222-2222-2222-222222222222"),
+		Battle: []model.BattleSummary{
+			{
+				ID:     uuid.MustParse("11111111-1111-1111-1111-111111111111"),
+				Planet: 4,
+				Shots:  17,
+			},
+			{
+				ID:     uuid.MustParse("22222222-2222-2222-2222-222222222222"),
+				Planet: 11,
+				Shots:  3,
+			},
 		},
 		Bombing: []*model.Bombing{
 			{

tools/local-dev/legacy-report/README.md

@@ -1,8 +1,25 @@
 # legacy-report-to-json
 
 Converts legacy text-format Galaxy turn reports (the *dg* and *gplus*
-engines that lived under `tools/local-dev/reports/`) into the JSON
-shape of [`pkg/model/report.Report`](../../../pkg/model/report).
+engines that lived under `tools/local-dev/reports/`) into a JSON
+envelope around [`pkg/model/report.Report`](../../../pkg/model/report)
+plus full `BattleReport`s (Phase 27).
+
+## Output envelope
+
+```jsonc
+{
+  "version": 1,
+  "report":  { /* report.Report */ },
+  "battles": { "<uuid>": { /* report.BattleReport */ }, ... }
+}
+```
+
+`version: 1` lets the UI distinguish a current-format envelope from a
+bare `Report` JSON. The synthetic-report loader accepts both — pre-
+envelope synthetic JSON files still load, just without battle
+fixtures. `battles` is omitted when the legacy file has no combat
+events.
 
 The output is consumed by the **DEV-only synthetic-report loader** on
 the UI client's lobby (`import.meta.env.DEV`). With it, the map view,
@@ -17,8 +34,8 @@ The tool is part of the synthetic-report parity rule documented in
 ```sh
 # from the repo root, with the Go workspace active
 go run ./tools/local-dev/legacy-report/cmd/legacy-report-to-json \
-    --in  tools/local-dev/reports/dg/KNNTS039.REP \
-    --out tools/local-dev/reports/dg/KNNTS039.json
+    --in  tools/local-dev/reports/dg/KNNTS041.REP \
+    --out tools/local-dev/reports/dg/KNNTS041.json
 ```
 
 `--in` reads `-` as stdin; `--out` defaults to stdout when empty or
@@ -68,6 +85,21 @@ already decodes from server responses
 | `LocalGroup[]`        | `Your Groups` (Phase 19)             |
 | `LocalFleet[]`        | `Your Fleets` (Phase 19)             |
 | `IncomingGroup[]`     | `Incoming Groups` (Phase 19)         |
+| `Battle[]` (summary)  | `Battle at (#N) Name` headers + `Battle Protocol` (Phase 27 follow-up) |
+
+The envelope's `battles` map carries the full `BattleReport`-s parsed
+out of the same blocks: every roster row turns into a
+`BattleReportGroup` (`Number`/`Tech`/`LoadType`/`LoadQuantity`/
+`NumberLeft`/`InBattle`), every `... fires on ... : Destroyed|Shields`
+line turns into a `BattleActionReport`. UUIDs are synthesised
+deterministically — `syntheticBattleID(idx)` for the battle
+identifier (per-report 0-based index, SHA1 namespace
+`be01a000-0000-0000-0000-000000000002`) and
+`syntheticBattleRaceID(name)` for `BattleReport.Races` entries (SHA1
+namespace `be01a000-0000-0000-0000-000000000003`). Re-running the
+converter on the same input file yields byte-identical JSON, so
+synthetic-mode UI URLs (`/games/synthetic-…/battle/<uuid>?turn=N`)
+stay stable across regenerations.
 
 Players whose name in the legacy file ends with `_RIP` are emitted with
 the suffix stripped and `Extinct: true`.
@@ -103,15 +135,9 @@ These exist in legacy reports but cannot be derived from the legacy
 text format at all. Each could become in-scope if a strong enough
 reason arises (see "Adding a new field" below).
 
-- Battles (`Battle at (#N) Name`, `Battle Protocol`) — the wire schema
-  carries battle UUIDs (`Report.Battle: []uuid.UUID`); the legacy text
-  carries per-battle rosters with stripped columns (no origin / range /
-  destination) and no stable identifier. Synthesising UUIDs from the
-  text would invent data that future Phase 27 work would have to drop;
-  the synthetic JSON therefore emits `battle: []`.
 - `OtherGroup[]` — no top-level legacy section. Foreign groups appear
-  only inside battle rosters (see above), with stripped columns; the
-  synthetic JSON emits `otherGroup: []`.
+  only inside battle rosters; the synthetic JSON emits
+  `otherGroup: []`.
 - `UnidentifiedGroup[]` — no legacy section at all; synthetic JSON
   emits `unidentifiedGroup: []`.
 - Cargo routes — no dedicated section in the legacy text format; the

tools/local-dev/legacy-report/cmd/legacy-report-to-json/main.go

@@ -1,7 +1,18 @@
 // Command legacy-report-to-json converts a legacy text-format Galaxy
-// turn report (the "dg" / "gplus" engines) into the JSON shape of
-// pkg/model/report.Report. The resulting file is what the UI client's
-// DEV-only synthetic-report loader on the lobby consumes.
+// turn report (the "dg" / "gplus" engines) into a JSON envelope
+// readable by the UI client's DEV-only synthetic-report loader:
+//
+//	{
+//	  "version": 1,
+//	  "report":  <Report JSON>,
+//	  "battles": { "<uuid>": <BattleReport JSON>, ... }
+//	}
+//
+// Carrying the per-turn report and the full BattleReports in one
+// payload lets the synthetic loader register the battles up-front
+// so the Battle Viewer can render any battle without a network
+// fetch. The bare Report shape (no envelope) the lobby loader
+// historically accepted remains backward-compatible on the UI side.
 package main
 
 import (
@@ -12,8 +23,18 @@ import (
 	"os"
 
 	legacyreport "galaxy/legacy-report"
+	"galaxy/model/report"
 )
 
+// envelope is the on-disk shape emitted by this CLI. `Version` lets
+// the UI loader distinguish a v1 envelope from a bare Report; future
+// versions can bump it without breaking older synthetic JSON files.
+type envelope struct {
+	Version int                            `json:"version"`
+	Report  report.Report                  `json:"report"`
+	Battles map[string]report.BattleReport `json:"battles,omitempty"`
+}
+
 func main() {
 	in := flag.String("in", "", "path to legacy .REP file (use - for stdin)")
 	out := flag.String("out", "", "path to write JSON to (use - or empty for stdout)")
@@ -31,7 +52,7 @@ func main() {
 	}
 	defer closeIn()
 
-	rep, err := legacyreport.Parse(r)
+	rep, battles, err := legacyreport.Parse(r)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "parse: %v\n", err)
 		os.Exit(1)
@@ -44,9 +65,17 @@ func main() {
 	}
 	defer closeOut()
 
+	env := envelope{Version: 1, Report: rep}
+	if len(battles) > 0 {
+		env.Battles = make(map[string]report.BattleReport, len(battles))
+		for i := range battles {
+			env.Battles[battles[i].ID.String()] = battles[i]
+		}
+	}
+
 	enc := json.NewEncoder(w)
 	enc.SetIndent("", "  ")
-	if err := enc.Encode(rep); err != nil {
+	if err := enc.Encode(env); err != nil {
 		fmt.Fprintf(os.Stderr, "encode: %v\n", err)
 		os.Exit(1)
 	}

tools/local-dev/legacy-report/parser.go

@@ -26,22 +26,29 @@ import (
 )
 
 // Parse reads a legacy text report and returns a [report.Report]
-// carrying the in-scope subset of fields. The Width and Height of the
-// returned report are both set to the legacy "Size" value (galaxies
-// are square in the legacy engines).
-func Parse(r io.Reader) (report.Report, error) {
+// carrying the in-scope subset of fields, plus the per-battle
+// [report.BattleReport] payloads parsed out of the "Battle at (#N)"
+// blocks. The Width and Height of the returned report are both set
+// to the legacy "Size" value (galaxies are square in the legacy
+// engines). The battle slice is empty when the legacy file carries
+// no combat events.
+func Parse(r io.Reader) (report.Report, []report.BattleReport, error) {
 	p := newParser()
 	sc := bufio.NewScanner(r)
 	sc.Buffer(make([]byte, 1024*1024), 4*1024*1024)
 	for sc.Scan() {
 		if err := p.handle(sc.Text()); err != nil {
-			return report.Report{}, err
+			return report.Report{}, nil, err
 		}
 	}
 	if err := sc.Err(); err != nil {
-		return report.Report{}, fmt.Errorf("legacyreport: scan: %w", err)
+		return report.Report{}, nil, fmt.Errorf("legacyreport: scan: %w", err)
 	}
-	return p.finish()
+	battles, err := p.finish()
+	if err != nil {
+		return report.Report{}, nil, err
+	}
+	return p.rep, battles, nil
 }
 
 type section int
@@ -63,6 +70,8 @@ const (
 	sectionOtherShipTypes
 	sectionBombings
 	sectionShipsInProduction
+	sectionBattle
+	sectionBattleProtocol
 )
 
 type parser struct {
@@ -85,6 +94,40 @@ type parser struct {
 	pendingFleets       []pendingFleet
 	pendingIncomings    []pendingIncoming
 	pendingShipProducts []pendingShipProduction
+
+	// Battle accumulator. `battles` collects every parsed BattleReport;
+	// `pendingBattle` carries the in-flight battle until its block
+	// ends (next "Battle at " header, a top-level section header, or
+	// end-of-file). `battleIndex` is the per-report 0-based index used
+	// to derive a stable synthetic UUID through `syntheticBattleID`.
+	// `pendingBattleRace` holds the race name currently being
+	// rostered, set by the "<Race> Groups" sub-header that opens each
+	// race's roster table inside the battle block.
+	battles           []report.BattleReport
+	pendingBattle     *pendingBattle
+	battleIndex       uint
+	pendingBattleRace string
+}
+
+type pendingBattle struct {
+	id         uuid.UUID
+	planet     uint
+	planetName string
+	// Race name → race index used in Protocol.{a,d}. Indices are
+	// 0-based and assigned in first-seen order across the battle.
+	raceIndex map[string]int
+	// (race name, class name) → ship-group index used in
+	// Protocol.{sa,sd}. Indices are 0-based and assigned in
+	// first-seen order across the battle, across all races.
+	shipIndex map[shipKey]int
+	races     map[int]uuid.UUID
+	ships     map[int]report.BattleReportGroup
+	protocol  []report.BattleActionReport
+}
+
+type shipKey struct {
+	race  string
+	class string
 }
 
 type pendingGroup struct {
@@ -155,10 +198,62 @@ func (p *parser) handle(line string) error {
 		return nil
 	}
 
+	// Inside a battle block, "<Race> Groups" lines open a per-race
+	// roster sub-table. The line matches singleTokenPrefix(_, " Groups")
+	// and would otherwise be treated as a top-level section transition
+	// by classifySection. Trap it here so the battle state stays open.
+	if (p.sec == sectionBattle || p.sec == sectionBattleProtocol) && p.pendingBattle != nil {
+		if race, ok := singleTokenPrefix(trimmed, " Groups"); ok {
+			// New roster — the protocol block, if it had started,
+			// cannot reopen; but the engine never emits "<Race> Groups"
+			// after "Battle Protocol" inside the same battle.
+			p.sec = sectionBattle
+			p.pendingBattleRace = race
+			p.skipHeader = true
+			return nil
+		}
+	}
+
 	if newSec, owner, isHeader := classifySection(trimmed); isHeader {
+		// Flush the previous battle on any header transition that
+		// moves us out of the battle block. Sub-transitions
+		// (sectionBattle → sectionBattleProtocol or vice-versa)
+		// inside the same battle do not flush.
+		switch {
+		case newSec == sectionBattle:
+			p.flushPendingBattle()
+			planet, planetName, ok := parseBattleHeader(trimmed)
+			if ok {
+				p.pendingBattle = &pendingBattle{
+					id:         syntheticBattleID(p.battleIndex),
+					planet:     planet,
+					planetName: planetName,
+					raceIndex:  make(map[string]int),
+					shipIndex:  make(map[shipKey]int),
+					races:      make(map[int]uuid.UUID),
+					ships:      make(map[int]report.BattleReportGroup),
+				}
+				p.battleIndex++
+			}
+			p.pendingBattleRace = ""
+		case newSec == sectionBattleProtocol:
+			// Stay in the same battle; the protocol header itself
+			// has no column header to skip — `Battle Protocol` is
+			// followed by the shot lines directly. Reset
+			// pendingBattleRace because the roster phase ended.
+			p.pendingBattleRace = ""
+		default:
+			// Any other section transition closes the battle.
+			p.flushPendingBattle()
+		}
 		p.sec = newSec
 		p.otherOwner = owner
-		p.skipHeader = newSec != sectionNone
+		// `Battle Protocol` has no column header to skip; ditto for
+		// the per-race `<Race> Groups` sub-header trapped above (we
+		// handle that branch separately). For sectionBattle the
+		// header line is "Battle at (#N) Name" with no following
+		// column row, so skipHeader stays false there as well.
+		p.skipHeader = newSec != sectionNone && newSec != sectionBattle && newSec != sectionBattleProtocol
 		return nil
 	}
 
@@ -205,16 +300,21 @@ func (p *parser) handle(line string) error {
 		p.parseBombing(fields)
 	case sectionShipsInProduction:
 		p.parseShipProductionRow(fields)
+	case sectionBattle:
+		p.parseBattleRosterRow(fields)
+	case sectionBattleProtocol:
+		p.parseBattleProtocolLine(fields)
 	}
 	return nil
 }
 
-func (p *parser) finish() (report.Report, error) {
+func (p *parser) finish() ([]report.BattleReport, error) {
 	if !p.sawHeader {
-		return report.Report{}, errors.New("legacyreport: missing report header line")
+		return nil, errors.New("legacyreport: missing report header line")
 	}
+	p.flushPendingBattle()
 	p.resolvePending()
-	return p.rep, nil
+	return p.battles, nil
 }
 
 // parseHeader extracts (race, turn) from
@@ -294,15 +394,16 @@ func classifySection(line string) (sec section, owner string, isHeader bool) {
 	case "Ships In Production":
 		return sectionShipsInProduction, "", true
 	case "Approaching Groups",
-		"Broadcast Message",
-		"Battle Protocol":
+		"Broadcast Message":
 		return sectionNone, "", true
+	case "Battle Protocol":
+		return sectionBattleProtocol, "", true
 	}
 	if strings.HasPrefix(line, "Status of Players") {
 		return sectionStatusOfPlayers, "", true
 	}
 	if strings.HasPrefix(line, "Battle at ") {
-		return sectionNone, "", true
+		return sectionBattle, "", true
 	}
 	if strings.HasPrefix(line, "=== ATTENTION") {
 		return sectionNone, "", true
@@ -637,6 +738,227 @@ func (p *parser) parseBombing(fields []string) {
 	})
 }
 
+// parseBattleHeader extracts (planet, planetName) from a
+// "Battle at (#N) <PlanetName>" line. The planet number is the
+// integer between "(#" and ")"; the planet name is the rest of the
+// line after the closing parenthesis (trimmed).
+func parseBattleHeader(line string) (uint, string, bool) {
+	const prefix = "Battle at "
+	if !strings.HasPrefix(line, prefix) {
+		return 0, "", false
+	}
+	rest := strings.TrimSpace(line[len(prefix):])
+	if !strings.HasPrefix(rest, "(#") {
+		return 0, "", false
+	}
+	closing := strings.IndexByte(rest, ')')
+	if closing < 0 {
+		return 0, "", false
+	}
+	num, err := strconv.ParseUint(rest[2:closing], 10, 32)
+	if err != nil {
+		return 0, "", false
+	}
+	name := strings.TrimSpace(rest[closing+1:])
+	return uint(num), name, true
+}
+
+// parseBattleRosterRow consumes one ship-group line from a battle
+// roster sub-table. Columns (10 tokens; the last is the per-group
+// state word):
+//
+//	#  T          D     W     S    C  T  Q   L  state
+//	1  Pistolet  1.6  1.00  1.00  0  -  0   1  In_Battle
+//
+// where column "L" carries the number of ships remaining after the
+// battle (confirmed against KNNTS fixtures). Rows are appended to
+// `pendingBattle.ships` under the race name currently held in
+// `pendingBattleRace`.
+func (p *parser) parseBattleRosterRow(fields []string) {
+	if p.pendingBattle == nil || p.pendingBattleRace == "" {
+		return
+	}
+	if len(fields) < 10 {
+		return
+	}
+	number, err := strconv.ParseUint(fields[0], 10, 32)
+	if err != nil {
+		return
+	}
+	className := fields[1]
+	drive, _ := parseFloat(fields[2])
+	weapons, _ := parseFloat(fields[3])
+	shields, _ := parseFloat(fields[4])
+	cargo, _ := parseFloat(fields[5])
+	loadQuantity, _ := parseFloat(fields[7])
+	numLeft, err := strconv.ParseUint(fields[8], 10, 32)
+	if err != nil {
+		return
+	}
+	state := fields[9]
+	tech := make(map[string]report.Float, 4)
+	if drive != 0 {
+		tech["DRIVE"] = report.F(drive)
+	}
+	if weapons != 0 {
+		tech["WEAPONS"] = report.F(weapons)
+	}
+	if shields != 0 {
+		tech["SHIELDS"] = report.F(shields)
+	}
+	if cargo != 0 {
+		tech["CARGO"] = report.F(cargo)
+	}
+
+	p.assignRaceIndex(p.pendingBattleRace)
+	key := shipKey{race: p.pendingBattleRace, class: className}
+	idx := p.assignShipIndex(key)
+
+	// Legacy battle rosters may list the same `(race, className)`
+	// across multiple rows — different tech variants, ships pulled
+	// from several stacks / planets, etc. We collapse those rows
+	// into one BattleReportGroup keyed by `(race, className)` (the
+	// viewer aggregates per class anyway) by SUMMING Number and
+	// NumberLeft instead of overwriting; otherwise only the last
+	// row's counts survive and the battle protocol's destroy count
+	// would dwarf the recorded initial count (the original
+	// motivation for the now-removed "phantom destroy" workaround).
+	if existing, found := p.pendingBattle.ships[idx]; found {
+		existing.Number += uint(number)
+		existing.NumberLeft += uint(numLeft)
+		// LoadQuantity is per-ship cargo — average is a fair fallback
+		// when several stacks of the same class merge into one bucket.
+		existing.LoadQuantity = report.F(
+			(existing.LoadQuantity.F() + loadQuantity) / 2,
+		)
+		// Tech / LoadType / InBattle keep their first-seen values:
+		// the viewer treats them as bucket-wide attributes and the
+		// first row is normally the most representative tech variant.
+		p.pendingBattle.ships[idx] = existing
+		return
+	}
+
+	p.pendingBattle.ships[idx] = report.BattleReportGroup{
+		Race:         p.pendingBattleRace,
+		ClassName:    className,
+		Tech:         tech,
+		Number:       uint(number),
+		NumberLeft:   uint(numLeft),
+		LoadType:     dashOrEmpty(fields[6]),
+		LoadQuantity: report.F(loadQuantity),
+		InBattle:     state == "In_Battle",
+	}
+}
+
+// parseBattleProtocolLine consumes one shot line of the
+// "Battle Protocol" sub-block. Required shape (8 tokens):
+//
+//	<atkRace> <atkClass> fires on <defRace> <defClass> : <Destroyed|Shields>
+//
+// Anything else (including the empty line separating the protocol
+// from the preceding rosters) is silently skipped — the engine never
+// emits other text inside this block.
+func (p *parser) parseBattleProtocolLine(fields []string) {
+	if p.pendingBattle == nil {
+		return
+	}
+	if len(fields) != 8 {
+		return
+	}
+	if fields[2] != "fires" || fields[3] != "on" || fields[6] != ":" {
+		return
+	}
+	atkRace, atkClass := fields[0], fields[1]
+	defRace, defClass := fields[4], fields[5]
+	destroyed := fields[7] == "Destroyed"
+
+	aRace := p.assignRaceIndex(atkRace)
+	dRace := p.assignRaceIndex(defRace)
+	sa := p.assignShipIndex(shipKey{race: atkRace, class: atkClass})
+	sd := p.assignShipIndex(shipKey{race: defRace, class: defClass})
+
+	// Synthesise a minimal BattleReportGroup entry when the shot
+	// references a (race, class) pair that the roster did not
+	// declare. This happens when the legacy emitter trims a roster
+	// row but the engine logged a shot for that group.
+	if _, ok := p.pendingBattle.ships[sa]; !ok {
+		p.pendingBattle.ships[sa] = report.BattleReportGroup{
+			Race: atkRace, ClassName: atkClass, InBattle: true,
+			Tech: map[string]report.Float{},
+		}
+	}
+	if _, ok := p.pendingBattle.ships[sd]; !ok {
+		p.pendingBattle.ships[sd] = report.BattleReportGroup{
+			Race: defRace, ClassName: defClass, InBattle: true,
+			Tech: map[string]report.Float{},
+		}
+	}
+
+	p.pendingBattle.protocol = append(p.pendingBattle.protocol, report.BattleActionReport{
+		Attacker:          aRace,
+		AttackerShipClass: sa,
+		Defender:          dRace,
+		DefenderShipClass: sd,
+		Destroyed:         destroyed,
+	})
+}
+
+// assignRaceIndex returns the in-battle race index for raceName,
+// creating a new entry on first sight. Race indices are 0-based and
+// monotonically increasing in first-seen order. The synthetic race
+// UUID is derived from the race name through
+// `syntheticBattleRaceNamespace`.
+func (p *parser) assignRaceIndex(raceName string) int {
+	if idx, ok := p.pendingBattle.raceIndex[raceName]; ok {
+		return idx
+	}
+	idx := len(p.pendingBattle.raceIndex)
+	p.pendingBattle.raceIndex[raceName] = idx
+	p.pendingBattle.races[idx] = syntheticBattleRaceID(raceName)
+	return idx
+}
+
+// assignShipIndex returns the in-battle ship-group index for
+// (race, class), creating a new entry on first sight. Indices are
+// 0-based and monotonically increasing in first-seen order across
+// all races.
+func (p *parser) assignShipIndex(key shipKey) int {
+	if idx, ok := p.pendingBattle.shipIndex[key]; ok {
+		return idx
+	}
+	idx := len(p.pendingBattle.shipIndex)
+	p.pendingBattle.shipIndex[key] = idx
+	return idx
+}
+
+// flushPendingBattle finalises the in-flight battle: appends the
+// BattleReport to `p.battles` and a matching BattleSummary
+// (id/planet/shots) to `p.rep.Battle`. No-op when no battle is
+// pending. Idempotent — clears `pendingBattle` on completion.
+func (p *parser) flushPendingBattle() {
+	if p.pendingBattle == nil {
+		return
+	}
+	pb := p.pendingBattle
+	p.pendingBattle = nil
+	p.pendingBattleRace = ""
+
+	br := report.BattleReport{
+		ID:         pb.id,
+		Planet:     pb.planet,
+		PlanetName: pb.planetName,
+		Races:      pb.races,
+		Ships:      pb.ships,
+		Protocol:   pb.protocol,
+	}
+	p.battles = append(p.battles, br)
+	p.rep.Battle = append(p.rep.Battle, report.BattleSummary{
+		ID:     pb.id,
+		Planet: pb.planet,
+		Shots:  uint(len(pb.protocol)),
+	})
+}
+
 // parseShipProductionRow buffers a "Ships In Production" row for
 // post-processing in [parser.finish]. Columns:
 //
@@ -957,6 +1279,31 @@ func syntheticGroupID(g uint) uuid.UUID {
 	return uuid.NewSHA1(syntheticGroupNamespace, fmt.Appendf(nil, "legacy-local-group-%d", g))
 }
 
+// syntheticBattleNamespace seeds [uuid.NewSHA1] for the per-report
+// battle-index → UUID derivation used by `Report.Battle[i].ID` and
+// `BattleReport.ID`. Distinct from `syntheticGroupNamespace` so a
+// per-report battle index can never collide with a ship-group id.
+// Mirrors the rationale in `syntheticGroupNamespace`: arbitrary
+// value, stable across releases.
+var syntheticBattleNamespace = uuid.MustParse("be01a000-0000-0000-0000-000000000002")
+
+// syntheticBattleRaceNamespace seeds [uuid.NewSHA1] for the
+// per-battle race name → race UUID derivation that fills
+// `BattleReport.Races`. Engine-side reports carry the real race
+// UUID; the legacy text only carries the race name, so we derive a
+// stable identifier from the name. The constant is independent of
+// `syntheticBattleNamespace` so race UUIDs can never collide with
+// battle UUIDs.
+var syntheticBattleRaceNamespace = uuid.MustParse("be01a000-0000-0000-0000-000000000003")
+
+func syntheticBattleID(idx uint) uuid.UUID {
+	return uuid.NewSHA1(syntheticBattleNamespace, fmt.Appendf(nil, "legacy-battle-%d", idx))
+}
+
+func syntheticBattleRaceID(name string) uuid.UUID {
+	return uuid.NewSHA1(syntheticBattleRaceNamespace, fmt.Appendf(nil, "legacy-battle-race-%s", name))
+}
+
 func dashOrEmpty(s string) string {
 	if s == "-" {
 		return ""

tools/local-dev/legacy-report/parser_test.go

@@ -18,7 +18,7 @@ func TestParseHeaderAndSize(t *testing.T) {
 		"",
 	}, "\n")
 
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -54,7 +54,7 @@ func TestParseStatusOfPlayers(t *testing.T) {
 		"",
 	}, "\n")
 
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -87,7 +87,7 @@ func TestParseYourVote(t *testing.T) {
 		"KnightErrants  16.02",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -115,7 +115,7 @@ func TestParseLocalAndOtherPlanets(t *testing.T) {
 		" 12  303.84  579.23  Skarabei  500.00  500.00  500.00  10.00  Capital     0.00   70.99  20.03  341.78",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -160,7 +160,7 @@ func TestParseUninhabitedAndUnidentified(t *testing.T) {
 		"  1  579.12  489.37",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -196,7 +196,7 @@ func TestParseShipClasses(t *testing.T) {
 		"Dragon  16.70   1   1.10   1.00  1   19.80",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -241,7 +241,7 @@ func TestParseSciences(t *testing.T) {
 		"_Drift         1    0    0    0",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -280,7 +280,7 @@ func TestParseBombings(t *testing.T) {
 		"Knights        Ricksha  332  PEHKE   500.00 258.64  Dron 184.39   0.00  6.42   331.93  Damaged",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -339,7 +339,7 @@ func TestParseShipsInProduction(t *testing.T) {
 		" 17  Castle   CombatFlame  990.10  0.07  1000.00",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -381,7 +381,7 @@ func TestParseShipsInProductionDropsUnknownPlanet(t *testing.T) {
 		" 99  Lost   Frigate  100.00  0.05  500.00",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -391,23 +391,57 @@ func TestParseShipsInProductionDropsUnknownPlanet(t *testing.T) {
 	}
 }
 
-// TestParseSkipsBattles covers the only remaining legacy section the
-// parser ignores: "Battle at ..." headers and the following "Battle
-// Protocol" block. Bombings, Ships In Production, and the per-race
-// Sciences / Ship Types blocks now flow through real parsers; the
-// dedicated section tests below cover them.
-func TestParseSkipsBattles(t *testing.T) {
+// TestParseBattles exercises the battle-block parser end-to-end:
+// two battles with two races each, full rosters, and protocols. The
+// inline fixture mirrors the KNNTS-style layout (race-named roster
+// sub-headers, 10-column roster rows, 8-token shot lines) so any
+// drift from the real engine format breaks this test before a smoke
+// regression. Asserts:
+//   - report.Battle carries one BattleSummary per "Battle at"
+//   - BattleReport slice mirrors that with full Races/Ships/Protocol
+//   - Battle Protocol "Foo fires on Bar : <Destroyed|Shields>" lines
+//     map to BattleActionReport entries with the correct destroyed flag
+//   - Roster column 8 (the "L" column) populates NumberLeft
+//   - Top-level sections after a battle (Your Planets) still parse
+//     — battle state must close cleanly without leaking rows.
+func TestParseBattles(t *testing.T) {
 	in := strings.Join([]string{
 		"Race Report for Galaxy PLUS Turn 1",
 		"",
 		"Battle at (#7) B-007",
 		"",
-		"#  T          D  W  S  C  T  Q  L",
-		"1  PeaceShip  4  0  0  0  -  0  1  Out_Battle",
+		"Foo Groups",
+		"",
+		"#  T            D  W  S  C  T  Q  L",
+		"1  PeaceShip  4.0  0  0  0  -  0  1  In_Battle",
+		"2  Drone      0.0  1  1  0  -  0  0  In_Battle",
+		"",
+		"Bar Groups",
+		"",
+		"#  T          D     W  S  C  T  Q  L",
+		"1  Pistolet  1.0  1.0  0  0  -  0  1  In_Battle",
 		"",
 		"Battle Protocol",
 		"",
-		"Foo fires on Bar : Destroyed",
+		"Foo  PeaceShip  fires  on  Bar  Pistolet  :  Shields",
+		"Bar  Pistolet  fires  on  Foo  Drone  :  Destroyed",
+		"Bar  Pistolet  fires  on  Foo  Drone  :  Destroyed",
+		"",
+		"Battle at (#11) X-011",
+		"",
+		"Foo Groups",
+		"",
+		"#  T          D  W  S  C  T  Q  L",
+		"1  Scout    1.0  0  0  0  -  0  1  In_Battle",
+		"",
+		"Bar Groups",
+		"",
+		"#  T          D  W  S  C  T  Q  L",
+		"1  Sniper   2.0  1  0  0  -  0  0  In_Battle",
+		"",
+		"Battle Protocol",
+		"",
+		"Foo  Scout  fires  on  Bar  Sniper  :  Destroyed",
 		"",
 		"Your Planets",
 		"",
@@ -415,15 +449,187 @@ func TestParseSkipsBattles(t *testing.T) {
 		" 17  171.05  700.24  Castle  1000.00  1000.00  1000.00  10.00  Capital  0.00    0.68   88.78  1000.00",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, battles, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
+
+	// The trailing Your Planets section must still parse — battle
+	// state must close before the next top-level header.
 	if got, want := len(rep.LocalPlanet), 1; got != want {
-		t.Fatalf("len(LocalPlanet) = %d, want %d (battle rows must not leak in)", got, want)
+		t.Fatalf("len(LocalPlanet) = %d, want %d (battle state did not close)", got, want)
 	}
-	if got, want := len(rep.Battle), 0; got != want {
-		t.Errorf("len(Battle) = %d, want %d (legacy parser does not synthesise battle UUIDs)", got, want)
+
+	if got, want := len(rep.Battle), 2; got != want {
+		t.Fatalf("len(rep.Battle) = %d, want %d", got, want)
+	}
+	if got, want := len(battles), 2; got != want {
+		t.Fatalf("len(battles) = %d, want %d", got, want)
+	}
+
+	// First battle: planet 7, 3 shots; protocol shape with one
+	// shielded shot and two destroyed shots.
+	b0 := battles[0]
+	if b0.Planet != 7 || b0.PlanetName != "B-007" {
+		t.Errorf("battle[0] = (planet=%d, name=%q), want (7, %q)",
+			b0.Planet, b0.PlanetName, "B-007")
+	}
+	if got, want := len(b0.Protocol), 3; got != want {
+		t.Fatalf("battle[0].Protocol = %d shots, want %d", got, want)
+	}
+	if b0.Protocol[0].Destroyed {
+		t.Errorf("battle[0].Protocol[0].Destroyed = true (Shields hit), want false")
+	}
+	if !b0.Protocol[1].Destroyed || !b0.Protocol[2].Destroyed {
+		t.Errorf("battle[0].Protocol[1..2].Destroyed must be true (Destroyed hits)")
+	}
+
+	// First battle: roster size and NumberLeft mapping.
+	if got, want := len(b0.Ships), 3; got != want {
+		t.Fatalf("battle[0].Ships = %d groups, want %d", got, want)
+	}
+	// 'Drone' has NumberLeft=0 in the roster (column 8 = 0). The
+	// protocol corroborates: Pistolet destroyed Drone twice.
+	dronePresent := false
+	for _, ship := range b0.Ships {
+		if ship.ClassName == "Drone" {
+			dronePresent = true
+			if ship.NumberLeft != 0 {
+				t.Errorf("Drone.NumberLeft = %d, want 0", ship.NumberLeft)
+			}
+			if ship.Number != 2 {
+				t.Errorf("Drone.Number = %d, want 2", ship.Number)
+			}
+		}
+	}
+	if !dronePresent {
+		t.Errorf("Drone roster row not parsed into battle[0].Ships")
+	}
+
+	// Summary mirrors the BattleReport ID and shot count.
+	if rep.Battle[0].ID != b0.ID {
+		t.Errorf("rep.Battle[0].ID = %s, want %s", rep.Battle[0].ID, b0.ID)
+	}
+	if rep.Battle[0].Shots != 3 {
+		t.Errorf("rep.Battle[0].Shots = %d, want 3", rep.Battle[0].Shots)
+	}
+	if rep.Battle[0].Planet != 7 {
+		t.Errorf("rep.Battle[0].Planet = %d, want 7", rep.Battle[0].Planet)
+	}
+
+	// Second battle: planet 11, 1 shot.
+	if rep.Battle[1].Planet != 11 || rep.Battle[1].Shots != 1 {
+		t.Errorf("rep.Battle[1] = (planet=%d, shots=%d), want (11, 1)",
+			rep.Battle[1].Planet, rep.Battle[1].Shots)
+	}
+
+	// Battle IDs are stable across re-parses.
+	rep2, battles2, err := Parse(strings.NewReader(in))
+	if err != nil {
+		t.Fatalf("Parse (second pass): %v", err)
+	}
+	if rep.Battle[0].ID != rep2.Battle[0].ID || battles[0].ID != battles2[0].ID {
+		t.Errorf("battle id must be deterministic across re-parses")
+	}
+}
+
+// TestParseBattleAggregatesDuplicateClasses guards against the
+// regression that produced the original "phantom destroys" symptom:
+// the same `(race, className)` pair appearing on multiple roster
+// rows must collapse into a single BattleReportGroup whose `Number`
+// (the "#" column, initial ship count) and `NumberLeft` (the "L"
+// column, survivors) are the sums across rows. Without the
+// aggregation only the last row's counts survived and the protocol's
+// destroy count dwarfed the recorded initial count (e.g. KNNTS041
+// turn-41 planet #7 lists `pup` seven separate times: 99 + 105 + 291 +
+// 287 + 166 + 132 + 88 = 1168 ships, 86 survivors, 1082 destroys).
+func TestParseBattleAggregatesDuplicateClasses(t *testing.T) {
+	in := strings.Join([]string{
+		"Race Report for Galaxy PLUS Turn 1",
+		"",
+		"Battle at (#7) B-007",
+		"",
+		"Foo Groups",
+		"",
+		" #  T          D    W  S  C  T  Q  L",
+		" 3  Drone    1.0  1.0  0  0  -  0  1  In_Battle",
+		" 4  Drone    1.2  1.0  0  0  -  0  2  In_Battle",
+		"10  Cruiser  3.0  2.0  0  0  -  0  9  In_Battle",
+		"",
+		"Bar Groups",
+		"",
+		"#  T          D    W  S  C  T  Q  L",
+		"5  Pistolet 1.0  1.0  0  0  -  0  3  In_Battle",
+		"",
+		"Battle Protocol",
+		"",
+		"Bar  Pistolet  fires  on  Foo  Drone  :  Destroyed",
+		"Bar  Pistolet  fires  on  Foo  Drone  :  Destroyed",
+		"Bar  Pistolet  fires  on  Foo  Drone  :  Destroyed",
+		"Bar  Pistolet  fires  on  Foo  Drone  :  Destroyed",
+		"",
+	}, "\n")
+
+	rep, battles, err := Parse(strings.NewReader(in))
+	if err != nil {
+		t.Fatalf("Parse: %v", err)
+	}
+	if got, want := len(battles), 1; got != want {
+		t.Fatalf("len(battles) = %d, want %d", got, want)
+	}
+	b := battles[0]
+
+	// The three Foo roster rows collapse into two BattleReportGroup
+	// entries: one Foo:Drone (rows 1+2) and one Foo:Cruiser (row 3),
+	// plus one Bar:Pistolet. Total 3 groups, NOT 4.
+	if got, want := len(b.Ships), 3; got != want {
+		t.Fatalf("battle.Ships = %d groups, want %d (duplicate class rows must merge)", got, want)
+	}
+
+	var drone, cruiser, pistolet *report.BattleReportGroup
+	for i := range b.Ships {
+		g := b.Ships[i]
+		switch g.ClassName {
+		case "Drone":
+			drone = &g
+		case "Cruiser":
+			cruiser = &g
+		case "Pistolet":
+			pistolet = &g
+		}
+	}
+	if drone == nil || cruiser == nil || pistolet == nil {
+		t.Fatalf("missing class: drone=%v cruiser=%v pistolet=%v", drone, cruiser, pistolet)
+	}
+
+	// Drone rows sum to Number = 3 + 4 = 7 and NumberLeft = 1 + 2 = 3.
+	// Protocol corroborates: four Destroyed shots against Drone, so
+	// 7 - 3 = 4 — the protocol's destroy count reconciles with the
+	// recorded delta only when both rows are summed.
+	if drone.Number != 7 {
+		t.Errorf("Drone.Number = %d, want 7 (3+4)", drone.Number)
+	}
+	if drone.NumberLeft != 3 {
+		t.Errorf("Drone.NumberLeft = %d, want 3 (1+2)", drone.NumberLeft)
+	}
+	// Cruiser and Pistolet are single-row classes — counts must match
+	// the file verbatim with no spurious merging across classes.
+	if cruiser.Number != 10 || cruiser.NumberLeft != 9 {
+		t.Errorf("Cruiser = (Number=%d, NumberLeft=%d), want (10, 9)",
+			cruiser.Number, cruiser.NumberLeft)
+	}
+	if pistolet.Number != 5 || pistolet.NumberLeft != 3 {
+		t.Errorf("Pistolet = (Number=%d, NumberLeft=%d), want (5, 3)",
+			pistolet.Number, pistolet.NumberLeft)
+	}
+
+	// rep-level summary must reflect the merged shape: 4 shots, one
+	// battle, no crash or spurious extra battles.
+	if got, want := len(rep.Battle), 1; got != want {
+		t.Fatalf("len(rep.Battle) = %d, want %d", got, want)
+	}
+	if rep.Battle[0].Shots != 4 {
+		t.Errorf("rep.Battle[0].Shots = %d, want 4", rep.Battle[0].Shots)
 	}
 }
 
@@ -451,7 +657,7 @@ func TestParseYourGroups(t *testing.T) {
 		"  2   1  Tormoz    11.19  0.00  0.00  1.0  CAP  4  North   Castle 7.5  60.66   49.50  -    In_Space",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -515,7 +721,7 @@ func TestParseYourFleets(t *testing.T) {
 		" 1  Far    2  North   Castle  4.50  20  In_Space",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -564,7 +770,7 @@ func TestParseIncomingGroups(t *testing.T) {
 		" 87  169.59  694.49  North    500.00   500.00   500.00  10.00  Capital  0.00    0.52   35.76   500.00",
 		"",
 	}, "\n")
-	rep, err := Parse(strings.NewReader(in))
+	rep, _, err := Parse(strings.NewReader(in))
 	if err != nil {
 		t.Fatalf("Parse: %v", err)
 	}
@@ -597,11 +803,12 @@ type smokeWant struct {
 	localGroups, localFleets, incomingGroups      int
 	localScience, otherScience, otherShipClass    int
 	bombings, shipProductions                     int
+	battles                                       int
 }
 
 func runSmoke(t *testing.T, path string, want smokeWant) {
 	t.Helper()
-	rep, err := parseFile(t, path)
+	rep, battles, err := parseFile(t, path)
 	if err != nil {
 		if os.IsNotExist(err) {
 			t.Skipf("legacy report fixture missing: %s", path)
@@ -647,12 +854,31 @@ func runSmoke(t *testing.T, path string, want smokeWant) {
 		{"OtherShipClass", len(rep.OtherShipClass), want.otherShipClass},
 		{"Bombing", len(rep.Bombing), want.bombings},
 		{"ShipProduction", len(rep.ShipProduction), want.shipProductions},
+		{"Battle (summary)", len(rep.Battle), want.battles},
+		{"BattleReport", len(battles), want.battles},
 	}
 	for _, c := range checks {
 		if c.got != c.want {
 			t.Errorf("%s = %d, want %d", c.name, c.got, c.want)
 		}
 	}
+	for i, summary := range rep.Battle {
+		if i >= len(battles) {
+			break
+		}
+		if summary.ID != battles[i].ID {
+			t.Errorf("battle[%d].ID summary=%s vs report=%s",
+				i, summary.ID, battles[i].ID)
+		}
+		if summary.Shots != uint(len(battles[i].Protocol)) {
+			t.Errorf("battle[%d].Shots = %d, want %d (len(Protocol))",
+				i, summary.Shots, len(battles[i].Protocol))
+		}
+		if summary.Planet != battles[i].Planet {
+			t.Errorf("battle[%d].Planet summary=%d vs report=%d",
+				i, summary.Planet, battles[i].Planet)
+		}
+	}
 }
 
 // TestParseDgKNNTS039 is a smoke test: the parser must produce
@@ -676,6 +902,7 @@ func TestParseDgKNNTS039(t *testing.T) {
 		otherShipClass:  170,
 		bombings:        16,
 		shipProductions: 6,
+		battles:         28,
 	})
 }
 
@@ -694,6 +921,7 @@ func TestParseDgKNNTS040(t *testing.T) {
 		otherShipClass:  160,
 		bombings:        24,
 		shipProductions: 16,
+		battles:         79,
 	})
 }
 
@@ -715,6 +943,7 @@ func TestParseDgKNNTS041(t *testing.T) {
 		otherShipClass:  218,
 		bombings:        12,
 		shipProductions: 22,
+		battles:         56,
 	})
 }
 
@@ -736,6 +965,7 @@ func TestParseGplus40(t *testing.T) {
 		otherShipClass:  183,
 		bombings:        4,
 		shipProductions: 8,
+		battles:         30,
 	})
 }
 
@@ -757,6 +987,7 @@ func TestParseDgKiller031(t *testing.T) {
 		otherShipClass:  161,
 		bombings:        18,
 		shipProductions: 0,
+		battles:         83,
 	})
 }
 
@@ -779,18 +1010,19 @@ func TestParseDgTancordia037(t *testing.T) {
 		otherShipClass:  123,
 		bombings:        22,
 		shipProductions: 20,
+		battles:         57,
 	})
 }
 
-func parseFile(t *testing.T, rel string) (report.Report, error) {
+func parseFile(t *testing.T, rel string) (report.Report, []report.BattleReport, error) {
 	t.Helper()
 	abs, err := filepath.Abs(rel)
 	if err != nil {
-		return report.Report{}, err
+		return report.Report{}, nil, err
 	}
 	f, err := os.Open(abs)
 	if err != nil {
-		return report.Report{}, err
+		return report.Report{}, nil, err
 	}
 	defer func() { _ = f.Close() }()
 	return Parse(f)

ui/PLAN.md

@@ -1381,9 +1381,13 @@ Decisions taken with the project owner during implementation:
 6. **`historyMode` as a prop, not a module.** Layout passes
    `historyMode={false}` (a constant in Phase 12) to `Sidebar` and
    `BottomTabs`; both forward to their tab-bar children which omit
-   the order entry when the flag is true. Phase 26 introduces the
-   real `lib/history-mode.ts` module and replaces the constant in
-   one place.
+   the order entry when the flag is true. Phase 26 superseded the
+   "introduce `lib/history-mode.ts`" half of this decision: the
+   single derivation `historyMode = $derived(gameState.historyMode)`
+   lives directly in `+layout.svelte`, the rune split between
+   `currentTurn` and `viewedTurn` lives in `GameStateStore`, and
+   no separate module is introduced. See Phase 26 decisions for
+   the rationale.
 7. **Empty-state copy is `order is empty` / `приказ пуст`.** The
    `coming soon` placeholder text is replaced; per-row delete
    button reads `delete` / `удалить`.
@@ -2581,99 +2585,340 @@ Decisions during stage:
     `game.table.*` so the two surfaces evolve independently. ≈90 new
     keys, en + ru in lockstep.
 
-## Phase 24. Push Events — Turn-Ready
+## ~~Phase 24. Push Events — Turn-Ready~~
 
-Status: pending.
+Status: done.
 
 Goal: subscribe to the server push stream and refresh client state
 when a turn-ready event arrives.
 
-Artifacts:
+Artifacts (delivered):
 
-- `ui/frontend/src/api/events.ts` push-stream subscription wired
-  through `GalaxyClient.subscribeEvents` and Connect server-streaming
-- on `game.turn.ready` event: invalidate `(game_id, current_turn)`
-  cache entries and trigger a fresh report fetch
-- a top-of-screen toast: `Turn N+1 is ready. View now.` with a button
-  that re-renders the active view against the new turn
-- mandatory event signature verification through `ui/core` — any
-  verification failure tears down the stream and reconnects with
-  exponential backoff
+- `ui/frontend/src/api/events.svelte.ts` — single
+  `SubscribeEvents` consumer per session. Absorbs the previous
+  `revocation-watcher.ts` (now deleted) so there is exactly one
+  authenticated stream per device session; clean end-of-stream and
+  `Unauthenticated` ConnectError both funnel into
+  `session.signOut("revoked")`. Exposes a `connectionStatus` rune
+  for the future header indicator.
+- `ui/frontend/src/lib/toast.svelte.ts` and `toast-host.svelte` —
+  single-slot transient-notification primitive mounted from the
+  root layout; later phases (battle, mail) reuse it.
+- `GameStateStore` gained `pendingTurn`, `markPendingTurn`,
+  `advanceToPending`, and a persisted `lastViewedTurn` so a boot
+  with `lastViewedTurn < currentTurn` opens the user on the
+  last-seen snapshot and surfaces the gap through the same toast
+  affordance as a live push event.
+- Backend producer: `lobby.Service.OnRuntimeSnapshot` emits
+  `game.turn.ready` on every `current_turn` advance, addressed to
+  every active membership, idempotency key
+  `turn-ready:<game_id>:<turn>`, payload `{game_id, turn}`.
+  Catalog routes it through the push channel only.
+- Mandatory event-signature verification through `ui/core`:
+  `core.verifyPayloadHash` + `core.verifyEvent` on every frame.
+  Verification failure tears the stream down and reconnects with
+  full-jitter exponential backoff (base 1 s, ceiling 30 s,
+  unbounded retries).
+- Topic doc: `ui/docs/events.md`.
 
 Dependencies: Phases 23, 4 (Connect streaming in gateway).
 
-Acceptance criteria:
+Decisions baked back in (this stage):
 
-- a server-side turn cutoff produces a toast within one second;
-- accepting the toast refreshes the active view to the new turn's data
-  without a full page reload;
-- a forged event (test fixture with bad signature) is rejected and the
-  stream reconnects.
+- **Minimum traffic on `game.turn.ready`.** The event flips
+  `gameState.pendingTurn` only; the report for the new turn is not
+  fetched until the user activates the toast's "view now" action.
+  This is the same affordance the boot-time `lastViewedTurn < currentTurn`
+  branch surfaces, so a player who returns after several turns sees
+  one "view now" path instead of an auto-jump.
+- **Revocation-watcher folded into `events.svelte.ts`.** A single
+  SubscribeEvents stream now serves both per-event dispatch and
+  revocation detection. Two parallel streams per session would
+  double the gateway hub load and ambiguate the
+  `session_invalidation` clean-close signal.
+- **Integration test scope.** Backend producer is covered by
+  `lobby/runtime_hooks_test.go` (testcontainers); UI consumer by
+  `tests/events.test.ts` and the Playwright e2e in
+  `tests/e2e/turn-ready.spec.ts`. A dedicated
+  `integration/turn_ready_flow_test.go` was not added because
+  triggering `OnRuntimeSnapshot` end-to-end through the running
+  runtime container would require a test-only admin endpoint, and
+  the existing `TestNotificationFlow_LobbyInvite` already exercises
+  the backend → gateway → stream path for another notification
+  kind on the exact same producer mechanism.
 
-Targeted tests:
+Acceptance criteria (met):
 
-- Vitest unit tests for `events.ts` handling subscribe, event
-  dispatch, error backoff;
-- Playwright e2e: trigger a server turn, observe toast and refresh.
+- a server-side turn cutoff produces a toast within one second
+  (Phase 24's stream propagation; the producer side ships with the
+  backend changes above);
+- activating the toast refreshes the active view to the new turn's
+  data without a full page reload
+  (`gameState.advanceToPending` → fresh `lobby.my.games.list` +
+  `user.games.report` round-trip);
+- a forged event (Vitest fixture with bad signature or
+  payload-hash mismatch) is rejected and the stream reconnects
+  through full-jitter backoff.
 
-## Phase 25. Sync Protocol — Order Queue, Retry, Conflict
+Targeted tests (delivered):
 
-Status: pending.
+- Vitest: `tests/events.test.ts` (verified dispatch, type
+  filtering, bad-signature reconnect, `Unauthenticated` sign-out,
+  clean end-of-stream sign-out, connection-status transitions);
+  `tests/toast.test.ts`; extensions in `tests/game-state.test.ts`
+  for `pendingTurn` / `lastViewedTurn` / `advanceToPending`.
+- Backend: `internal/notification/catalog_test.go` (kind +
+  channels); `internal/lobby/runtime_hooks_test.go`
+  (testcontainers, capturing publisher, idempotency on duplicate
+  snapshots).
+- Playwright: `tests/e2e/turn-ready.spec.ts` (signed
+  `game.turn.ready` frame surfaces the toast, manual dismiss
+  clears it).
 
-Goal: make the order draft survive network failures and turn cutoffs
-gracefully, with explicit user feedback on conflicts.
+## ~~Phase 25. Sync Protocol — Turn Cutoff, Conflict, Auto-Pause~~
 
-Artifacts:
+Status: done.
 
-- `ui/frontend/src/sync/order-queue.ts` send loop: on disconnect, hold
-  the most recent submit; on reconnect, retry once; on persistent
-  failure, surface error to the order tab
-- conflict detection: if the server returns `turn_already_closed` for
-  a submit, mark the entire draft as `conflict` and surface a
-  `Turn N closed before your order was accepted. Edit and resubmit.`
-  banner in the order tab
-- topic doc `ui/docs/sync-protocol.md` covering queue semantics,
-  retry budgets, and conflict UX
+Goal: make the order draft survive transient connectivity issues
+**and** the real turn-cutoff machinery, with explicit user feedback
+on conflicts and on admin-pause states. The phase is intentionally
+cross-module: the UI side leans on a backend turn-cutoff guard and
+auto-pause that did not exist before; both land together so the
+contract is end-to-end.
 
-Dependencies: Phases 14, 24.
+Decisions baked in during implementation:
+
+- Turn-cutoff enforcement lives in `backend` (not in `game-engine`).
+  The scheduler flips `runtime_status` to `generation_in_progress`
+  before each engine tick and back to `running` after; the
+  user-games handlers reject every command/order in
+  non-running runtime states.
+- A failed engine tick auto-pauses the game (`running → paused`)
+  through `lobby.OnRuntimeSnapshot`, and the lobby publishes a
+  matching `game.paused` push event. Admin resume remains the
+  only way out of `paused`.
+- The wire-level error codes are `turn_already_closed` (cutoff
+  conflict) and `game_paused` (paused / starting / finished / removed).
+  Gateway carries them through `projectUserBackendError` unchanged.
+- The UI draft store delegates to a new `OrderQueue` (single-slot
+  pending, single retry on reconnect via `onOnline` callback). On
+  `game.turn.ready` after a conflict / pause, the layout calls
+  `OrderDraftStore.resetForNewTurn` which wipes the draft and
+  re-hydrates from the server for the new turn (old commands are
+  preserved server-side and can be read back via
+  `user.games.order.get?turn=N`).
+
+Backend artifacts:
+
+- `backend/internal/notification/catalog.go`: new
+  `KindGamePaused = "game.paused"` and `catalog`/`SupportedKinds`
+  entries; matching `NotificationGamePaused` constant in
+  `backend/internal/lobby/lobby.go`; CHECK-constraint widened in
+  `backend/internal/postgres/migrations/00001_init.sql`.
+- `backend/internal/lobby/runtime_hooks.go`:
+  `nextStatusFromSnapshot` flips `running → paused` on
+  `engine_unreachable` / `generation_failed`; new
+  `publishGamePaused` mirrors `publishTurnReady`, idempotency key
+  `paused:<game_id>:<turn>`, payload `{game_id, turn, reason}`.
+- `backend/internal/runtime/scheduler.go`: `tick` wraps the engine
+  call with `generation_in_progress` / `running` flips and forwards
+  failure snapshots to lobby through
+  `Service.publishFailureSnapshot`.
+- `backend/internal/runtime/service.go`: `CheckOrdersAccept` plus
+  the pure `OrdersAcceptStatus` helper used by both `Orders` and
+  `Commands` user-games handlers.
+- `backend/internal/server/httperr/httperr.go`: new
+  `CodeTurnAlreadyClosed`, `CodeGamePaused`; openapi.yaml
+  `ErrorBody.code` enum extended.
+- `backend/internal/server/handlers_user_games.go`:
+  `requireOrdersOpen` runs before forwarding, maps sentinels to
+  HTTP 409 + the matching code.
+
+UI artifacts:
+
+- `ui/frontend/src/sync/order-queue.svelte.ts` (new) — `OrderQueue`
+  class with offline detection, classification of
+  `turn_already_closed` / `game_paused`, dependency-injected
+  online probe + event listeners. Pure-function helper
+  `classifyResult` reused from tests.
+- `ui/frontend/src/sync/order-types.ts` — `CommandStatus` gains
+  `conflict`.
+- `ui/frontend/src/sync/order-draft.svelte.ts` — wires
+  `OrderQueue` through `runSync`, adds `conflict` / `paused` /
+  `offline` to `SyncStatus`, plus `conflictBanner` /
+  `pausedBanner` runes, `markPaused`, `resetForNewTurn`,
+  `clearConflictForMutation`, sticky-`paused` guard in
+  `hydrateFromServer`. `bindClient(client, { getCurrentTurn })`
+  lets the conflict banner interpolate the turn number.
+- `ui/frontend/src/lib/sidebar/order-tab.svelte` — renders
+  conflict / paused banners and the new `conflict` per-row badge;
+  status bar carries the offline / conflict / paused copy.
+- `ui/frontend/src/lib/i18n/locales/{en,ru}.ts` — new keys for
+  `sync.{offline,conflict,paused}`, `conflict.banner`
+  (with `{turn}` interpolation) plus `banner_no_turn` fallback,
+  `paused.banner`, `status.conflict`.
+- `ui/frontend/src/routes/games/[id]/+layout.svelte` —
+  subscribes to `game.paused`; `game.turn.ready` handler now
+  triggers `resetForNewTurn` when the prior `syncStatus` was
+  `conflict` / `paused`. `bindClient` is invoked with
+  `getCurrentTurn: () => gameState.currentTurn`.
+- `ui/docs/sync-protocol.md` (new) — send-loop semantics, retry
+  budget, conflict and paused UX, recovery paths.
+- `ui/docs/order-composer.md` — stale Phase 25 paragraph
+  replaced with a pointer to the new topic doc; state-machine
+  diagram extended with the `conflict` transition.
+
+Dependencies: Phases 14, 24; backend notification / lobby /
+runtime modules.
 
 Acceptance criteria:
 
-- submitting an order while offline queues it and submits successfully
-  on reconnect;
-- a turn cutoff between draft and submit produces a visible conflict
-  banner with no data loss;
-- the order tab clearly distinguishes `draft`, `submitting`,
-  `accepted`, `rejected`, `conflict` states per command.
+- submitting an order while offline queues it and submits
+  successfully on reconnect (one attempt on the next `online`
+  event, no inline retry storm);
+- a turn cutoff between draft and submit produces a visible
+  conflict banner with the turn number; the local draft is
+  preserved until the next `game.turn.ready`, then the layout
+  wipes it and re-hydrates from the server for `turn = N+1`;
+- a runtime failure during generation flips the game into
+  `paused`, emits `game.paused`, and the order tab shows the
+  pause banner; submits are blocked until the next
+  `game.turn.ready` clears the state;
+- the order tab clearly distinguishes `draft`, `valid`,
+  `invalid`, `submitting`, `applied`, `rejected`, and
+  `conflict` states per command.
 
 Targeted tests:
 
-- Vitest unit tests for `order-queue` covering all state transitions;
-- Playwright e2e: simulate network drop using Playwright's offline
-  mode, submit an order, restore network, confirm submission;
-- regression test: force a turn cutoff during submit, assert conflict
-  banner appears.
+- Backend: `runtime_hooks_unit_test.go` for
+  `nextStatusFromSnapshot`, `orders_accept_test.go` for the
+  per-record decision, plus existing testcontainer-backed
+  `runtime_hooks_test.go` covering the published intent. Catalog
+  / event tests extended with `game.paused`.
+- UI Vitest: `tests/order-queue.test.ts` (classification +
+  offline plumbing), extended `tests/order-draft.test.ts`
+  (conflict marks commands, mutation clears banner, pause
+  blocks sync, offline holds + flushes on `online`,
+  `resetForNewTurn` re-hydrates), extended
+  `tests/order-tab.test.ts` (banner DOM + sync-status
+  attribute), extended `tests/events.test.ts` (`game.paused`
+  dispatch).
+- Playwright e2e: `tests/e2e/order-sync.spec.ts` — conflict
+  banner on `turn_already_closed` reply and paused banner on
+  the signed `game.paused` frame.
 
-## Phase 26. History Mode
+## ~~Phase 26. History Mode~~
 
-Status: pending.
+Status: done. Verified on local-ci run 6 (`success`, 2d17760).
 
 Goal: let the user navigate to past turns and view all data as it was,
 with no order composition allowed.
 
-Artifacts:
+Decisions baked in during implementation:
 
-- `ui/frontend/src/lib/header/turn-navigator.svelte` clickable turn
-  counter expansion: popover (desktop) / bottom-sheet (mobile) listing
-  recent turns and a search field for jumping to a turn number
-- `ui/frontend/src/lib/history-mode.ts` global toggle wired into every
-  view's data source: when active, all `state-binding`, table, report,
-  inspector, and map sources read from the historical snapshot for the
-  selected turn
-- `ui/frontend/src/lib/header/history-banner.svelte` persistent banner
-  reading `Viewing turn N · read-only` with a `Return to current turn`
-  action
-- order tab hidden in history mode (already prepared in Phase 12)
+1. **History state lives in `GameStateStore`, no separate module.**
+   The Phase 12 plan-line "introduce `lib/history-mode.ts`" is
+   superseded: the only consumer needs a one-line derivation
+   (`historyMode = $derived(gameState.historyMode)`), and the
+   project's compactness rule rejects an abstraction with no second
+   caller. The store ships two distinct turn runes — `currentTurn`
+   (server's authoritative latest, set by `setGame` /
+   `advanceToPending`) and `viewedTurn` (what the UI displays, set
+   by `viewTurn` / `returnToCurrent`) — plus the derived
+   `historyMode` rune that flips when `viewedTurn < currentTurn`.
+2. **`OrderDraftStore` gates mutations at one chokepoint.**
+   `bindClient` gains an optional `getHistoryMode: () => boolean`
+   alongside the existing `getCurrentTurn`; `add` / `remove` /
+   `move` return early when it reports `true`. Every Phase 14–22
+   inspector that calls `orderDraft.add(...)` becomes inert in
+   history mode without per-component edits.
+3. **Turn navigator UX.** Header replaces the static `turn N` text
+   with `← turn N →`: arrows step ±1 (disabled at `0` and
+   `currentTurn`), the middle button opens a dropdown of every
+   turn `Turn #0`…`Turn #currentTurn` with the current row carrying
+   a badge. No free-text input. Desktop uses an absolute popover
+   under the header; mobile reuses `view-menu.svelte`'s fixed-
+   drawer pattern (no new primitive). Selecting the current row
+   routes through `returnToCurrent()` so the "leave history" path
+   has one canonical entry.
+4. **History is ephemeral across reloads.** `last-viewed-turn` is
+   written only when `viewedTurn === currentTurn`; historical
+   excursions never advance the resume bookmark. Page reload exits
+   history mode. The visibility-refresh listener is a no-op while
+   `historyMode` is true so a tab-focus event cannot silently kick
+   the user back onto the live turn. Push events (Phase 24) continue
+   to deliver new-turn notifications, so the pending-turn toast
+   still appears.
+5. **Past-turn report cache.** New `game-history/{gameId}/turn/{N}`
+   namespace stores past-turn reports; `viewTurn(N)` reads cache
+   first and falls back to the network on miss. Past turns are
+   immutable so the cache has no TTL and no eviction. The current
+   turn deliberately skips the cache (it is mutable until the next
+   tick).
+6. **Order overlay short-circuits in history mode.**
+   `RenderedReportSource.report` returns the raw server snapshot
+   instead of running `applyOrderOverlay`: the draft is composed
+   against the current turn, projecting it onto a past report would
+   render fictional intent.
+7. **`game.shell.headline` removed.** The Phase 11 i18n key that
+   formatted `{race} @ {game}, turn {turn}` is deleted; the header
+   composes `race @ game` in plain text and delegates `turn N` to
+   `turn-navigator.svelte`. The existing `game-shell-headline`
+   testid moves to the `.left` wrapper so e2e specs that match
+   `toContainText("turn N")` continue to find the substring inside
+   the navigator's button.
+
+Artifacts (delivered):
+
+- `ui/frontend/src/lib/game-state.svelte.ts` — `viewedTurn` rune,
+  derived `historyMode` rune, `viewTurn(turn)` /
+  `returnToCurrent()` public methods, `loadTurn(turn, { isCurrent })`
+  refactor that gates `last-viewed-turn` writes, `readReport` cache
+  layer over the `game-history` namespace, visibility-refresh
+  short-circuit in history mode, `initSynthetic` keeps
+  `currentTurn === viewedTurn`.
+- `ui/frontend/src/sync/order-draft.svelte.ts` — `bindClient` accepts
+  `getHistoryMode`, `add` / `remove` / `move` no-op when active.
+- `ui/frontend/src/lib/rendered-report.svelte.ts` — overlay short-
+  circuit when `gameState.historyMode === true`.
+- `ui/frontend/src/lib/header/turn-navigator.svelte` (new) — header
+  triplet `← turn N →` + dropdown popover / drawer, reuses
+  `view-menu.svelte`'s outside-click / Escape pattern.
+- `ui/frontend/src/lib/header/history-banner.svelte` (new) — sticky
+  read-only banner under the header with a `Return to current turn`
+  action.
+- `ui/frontend/src/lib/header/header.svelte` — embeds
+  `<TurnNavigator />` next to the race-and-game identity span;
+  drops the static turn portion.
+- `ui/frontend/src/routes/games/[id]/+layout.svelte` —
+  `historyMode` derived rune, `getHistoryMode` passed to
+  `orderDraft.bindClient`, `<HistoryBanner />` mounted between
+  header and body.
+- `ui/frontend/src/lib/i18n/locales/{en,ru}.ts` — new
+  `game.shell.history.*` and `game.shell.turn.*` keys; the now-
+  unused `game.shell.headline` entry is removed.
+- `ui/docs/storage.md` — `game-history` namespace row; also adds
+  the `game-prefs/{gameId}/last-viewed-turn` row (Phase 11 doc
+  gap).
+- `ui/docs/game-state.md` — current/viewed-turn rune table, the
+  new History mode section.
+- `ui/docs/navigation.md` — describes the navigator, the read-only
+  banner, and the `historyMode` derivation wiring.
+- `ui/docs/order-composer.md` — notes the mutation gate, the
+  overlay short-circuit, and the cross-doc references.
+- Vitest: `tests/game-state.test.ts` extended with `viewTurn` /
+  `returnToCurrent` / `historyMode` derivation / cache hit /
+  visibility-refresh short-circuit / resume-from-stale-bookmark
+  flips; `tests/order-draft.test.ts` extended with the history-
+  mode gate cases; `tests/turn-navigator.test.ts` and
+  `tests/history-banner.test.ts` (new) cover the components in
+  isolation.
+- Playwright: `tests/e2e/history-mode.spec.ts` (new) — drives the
+  full chrome flow against `/games/<id>/table/planets`. The map
+  view is deliberately avoided because the Pixi renderer can
+  monopolise the headless Chromium main thread long enough to let
+  the `toContainText` poll find stale "turn ?" content; the table
+  view exercises the same wiring without that rendering tail.
 
 Dependencies: Phases 11, 12, 23.
 
@@ -2685,59 +2930,145 @@ Acceptance criteria:
   available;
 - returning to the current turn restores live data and re-shows the
   order tab with the prior draft intact (state preservation);
-- all UI views (map, tables, report, battle, mail) work in history
-  mode.
+- battle / mail stub views still render correctly while the
+  read-only banner is visible (Phases 27 / 28 will replace the
+  stubs with real implementations; the wiring is sufficient
+  today).
 
 Targeted tests:
 
-- Vitest unit tests for `history-mode` toggle and per-view source
-  selection;
-- Playwright e2e: enter history mode, navigate three views, return,
-  confirm the order draft survived.
+- Vitest unit tests for current/viewed turn rune split, view-turn
+  cache behaviour, visibility-refresh short-circuit, order-draft
+  history-mode gate, turn-navigator interactions, history-banner
+  rendering / action;
+- Playwright e2e: enter history mode via arrow, navigate via
+  dropdown, return via banner action, confirm the order draft
+  survives the round-trip.
 
-## Phase 27. Battle Viewer
+## ~~Phase 27. Battle Viewer~~
 
-Status: pending.
+Status: done (local-ci run 14).
 
-Goal: render battles as a dedicated view with playback controls
-(play, pause, step forward, step backward, rewind), driven by the
-server-side combat log; render battle and bombing markers on the map.
+Goal: ship a dedicated Battle Viewer rendering radial scenes from
+`BattleReport` data (planet centred, races on the outer ring, per
+ship-class clusters, animated shot lines), plus battle and bombing
+markers on the map. Battles and bombings stay strictly separate —
+bombings remain a static table in the Reports view, only battles
+get the animated viewer.
 
 Artifacts:
 
-- `ui/frontend/src/map/battle-markers.ts` renders markers on the map
-  for current-turn battles and bombings within visibility, clickable
-  to open the battle viewer
-- `ui/frontend/src/routes/games/[id]/battle/[battleId]/+page.svelte`
-  view with the combatant list, the round-by-round log, and a player
-  control bar
-- `ui/frontend/src/lib/battle-player/` round timeline, current-round
-  highlight, per-shot animation
-- entry points to the viewer: marker on map, row in the report's
-  battles section, push-event toast when a battle this turn involved
-  the player
-- topic doc `ui/docs/battle-viewer-ux.md` covering playback
-  semantics, accessibility (the combat log must be readable as text
-  for users who skip animations)
+- engine: `game/internal/router/handler/battle.go` for
+  `GET /api/v1/battle/:turn/:uuid` (handler pre-existed; Phase 27
+  added the tests + openapi schemas)
+- engine wire: `pkg/model/report/battle.go` ships a new
+  `BattleSummary{id, planet, shots}`; `Report.battle` carries a
+  slice of these summaries so the map can place markers without
+  fetching every full report
+- backend: `backend/internal/engineclient/client.go.FetchBattle`
+  and `backend/internal/server/handlers_user_games.go.Battle`
+  expose `GET /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}`
+- UI viewer: `ui/frontend/src/lib/battle-player/`
+  (`radial-layout.ts`, `timeline.ts`, `battle-scene.svelte`,
+  `playback-controls.svelte`, `battle-viewer.svelte`); SVG-based,
+  one frame per protocol entry, full controls (play/pause + step
+  back + step forward + rewind + 1x/2x/4x speed switch)
+- UI route + page wrapper:
+  `ui/frontend/src/routes/games/[id]/battle/[[battleId]]/+page.svelte`
+  feeds `gameId` / `turn` / `battleId` into
+  `ui/frontend/src/lib/active-view/battle.svelte`, which loads the
+  report via `api/battle-fetch.ts` (synthetic-fixture path + real
+  engine fetch through the backend gateway)
+- UI report link: `lib/active-view/report/section-battles.svelte`
+  now links every battle UUID into
+  `/games/{id}/battle/{uuid}?turn={turn}`
+- UI map markers: `ui/frontend/src/map/battle-markers.ts` emits a
+  yellow X cross per battle (two `LinePrim` through the planet's
+  bounding-square diagonals; stroke width scales 1px..5px with
+  protocol length) plus a stroke-only ring per bombing (yellow when
+  damaged, red when wiped). Wired into `state-binding.ts`; the map
+  click handler dispatches battle clicks to the viewer and bombing
+  clicks to a scroll-into-view of the matching row in Reports.
+- topic doc `ui/docs/battle-viewer-ux.md` covers playback
+  semantics, accessibility (the always-visible `<ol>` log), the
+  radial layout, and the marker click behaviour
+- docs/FUNCTIONAL.md §6.5 (Battle viewer) + mirror in
+  docs/FUNCTIONAL_ru.md
 
 Dependencies: Phase 23.
 
 Acceptance criteria:
 
 - battle and bombing markers render on the map for the seeded
-  current-turn report and are clickable to open the viewer;
-- the viewer plays back any battle in the seeded report including
-  multi-round and one-sided battles;
-- step controls allow precise inspection;
-- the same data is accessible as a static text log for accessibility.
+  current-turn report and are clickable: battle → Battle Viewer for
+  the corresponding UUID, bombing → scroll to its row in Reports;
+- the Battle Viewer plays back any `BattleReport` end-to-end with
+  step back / step forward / rewind / 1x-2x-4x speeds; observers
+  (`inBattle === false`) are not drawn; eliminated races drop out
+  and survivors re-distribute on the next frame;
+- the same protocol is mirrored as an always-visible text log under
+  the scene for accessibility;
+- bombings keep their Phase 23 static table layout in Reports; no
+  Battle Viewer entry-point is wired from them.
 
 Targeted tests:
 
-- Vitest unit tests for round-state transitions;
-- Vitest unit tests for marker rendering on torus and no-wrap
-  fixtures;
-- Playwright e2e: click a battle marker on the map, play through,
-  step backward, return to the report.
+- Vitest unit: radial layout (1/2/3 races) and timeline frame-
+  builder (initial state, shot decrement, race-elimination drop-out)
+  in `tests/battle-player.test.ts`
+- Vitest unit: marker primitives + stroke-width formula
+  (1→1, 50→2.98, 100→5, 200→5) in `tests/battle-markers.test.ts`
+- Go unit: engine HTTP handler validations (400 / 404 / 500) in
+  `game/internal/router/battle_test.go`
+- Go contract: openapi freezes for the new endpoint and schemas in
+  `game/openapi_contract_test.go`
+- Playwright e2e: click battle marker → viewer; play / step back;
+  click battle UUID in Reports → viewer; click bombing marker →
+  Reports bombings row scrolled into view.
+
+Decisions during stage:
+
+1. **Bombings stay a static table.** `section-bombings.svelte`
+   already covers the "who bombed, with what power, wiped or not"
+   requirement; nothing in Phase 27 touches it. Bombings explicitly
+   do not open the Battle Viewer.
+2. **Wire change.** `Report.Battle` switched from `[]uuid.UUID` to
+   `[]BattleSummary{id, planet, shots}` so the map renderer can
+   place markers without N extra fetches and so the cross-marker
+   stroke can scale with protocol length.
+3. **Battle marker = yellow X cross** drawn as 2 `LinePrim` through
+   the corners of the planet's circumscribed square; stroke width
+   `clamp(1 + (shots - 1) * 4 / 99, 1, 5)` px.
+4. **Bombing marker = stroke-only ring** slightly larger than the
+   planet circle. Yellow when damaged, red when wiped. Click =
+   scroll to the matching row in Reports (not the viewer).
+5. **Viewer URL** `/games/[id]/battle/[battleId]?turn=N`. Turn is a
+   query param so the same route works in history mode.
+6. **SVG, not PixiJS** for the radial scene — isolated component,
+   no need for WebGL; PixiJS stays as the map renderer.
+7. **Playback controls full set**: play / pause + step back + step
+   forward + rewind + 1x / 2x / 4x switch. 1x = 400 ms per frame.
+8. **Observer groups (`inBattle: false`)** are filtered out of both
+   the scene and the text log.
+9. **Cluster aggregation by `(race, className)`** so a race with
+   multiple groups of the same class collapses to one labelled
+   circle. Stable target for shot-line endpoints.
+10. **Page loader switches on `synthetic-` gameId prefix** —
+    synthetic mode uses `api/synthetic-battle.ts` fixtures; live
+    games hit `GET /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}`.
+    BattleViewer component itself is a logically isolated prop sink.
+11. **Always-visible `<ol>` text protocol** under the scene satisfies
+    the accessibility requirement without a separate "skip
+    animation" toggle.
+
+TODO carried into Phase 27 deferred items
+(see Phase 27 of this PLAN's deferred-followups list, near the
+bottom):
+
+- push event `game.battle.new` + toast deep-link;
+- richer ship-class visuals derived from class characteristics;
+- animated transitions when survivors re-distribute after an
+  elimination (currently hard-jumps).
 
 ## Phase 28. Diplomatic Mail View
 
@@ -3209,3 +3540,18 @@ phase listed in the parenthesis when that phase lands.
   exercises a unary Connect call and a server-streaming Connect call
   through `testenv.Bootstrap`. (Phase 7+, fold into the phase that
   needs it.)
+- **Battle viewer — push event `game.battle.new`** — when a battle
+  involving the current player lands, emit a backend notification
+  intent (idempotency `battle-new:<game_id>:<turn>:<battle_id>`,
+  payload `{game_id, turn, battle_id}`) so the in-game shell
+  surfaces a toast with a deep link into the Battle Viewer.
+  (Phase 27 deferred; needs an engine emit-side change.)
+- **Battle viewer — richer ship-class visuals** — current MVP draws
+  one small circle plus `<class>:<numLeft>` label per `(race,
+  className)` pair. Future work derives shape / scale from mass,
+  armament, shields, and the number of ships in the group.
+  (Phase 27 deferred.)
+- **Battle viewer — animated re-distribution on elimination** —
+  current implementation hard-jumps to the new spacing on the next
+  frame; replace with an easing so the survivors visibly slide
+  along the outer ring. (Phase 27 deferred.)

ui/docs/battle-viewer-ux.md

@@ -0,0 +1,258 @@
+# Battle Viewer UX
+
+Phase 27 ships a dedicated viewer for battles (`/games/<id>/battle/<battleId>`).
+Bombings stay where they were in Phase 23 — a static table in the
+Reports view (`section-bombings.svelte`). The two domains are
+deliberately not mixed in any visual surface or click target.
+
+## Data shape
+
+The `BattleViewer` component (`lib/battle-player/battle-viewer.svelte`)
+is logically isolated. It accepts a `BattleReport` matching
+`pkg/model/report/battle.go`. The fields it uses:
+
+- `id`, `planet`, `planetName` — header + the central-planet glyph.
+- `races: { [raceId]: raceUUID }` — race index space used by the
+  protocol's `a` / `d` fields.
+- `ships: { [groupKey]: BattleReportGroup }` — ship-group rosters
+  with `race` name, `className`, initial `num`, end-state `numLeft`,
+  and the `inBattle` flag. Observer groups (`inBattle: false`) are
+  never drawn.
+- `protocol: BattleActionReport[]` — flat list of shots. Each carries
+  attacker `(a, sa)`, defender `(d, sd)`, and `x` (destroyed?).
+
+The component asks `timeline.ts.buildFrames(report)` to expand the
+protocol into `protocol.length + 1` frames; frame 0 is the initial
+state and frame `N` reflects state after action `protocol[N-1]`. The
+race index per ship group is derived from the protocol itself —
+every in-battle group appears at least once as attacker or defender,
+and the engine never crosses these wires.
+
+## Radial scene
+
+The scene (`lib/battle-player/battle-scene.svelte`, SVG) places the
+planet at the centre and arrays the still-active races on an outer
+ring at equal angular spacing. Each race anchor hosts a *cloud* of
+class circles arranged on a Vogel sunflower spiral biased toward the
+planet (the cluster anchor is pushed inward by a quarter step so the
+rank-0 node — the heaviest group by NumberLeft — sits closest to the
+planet, and the spiral fans the rest behind it). When a race is
+wiped out, it drops out of the active list and the survivors are
+re-spaced on the next frame.
+
+Each class circle is one *bucket* keyed by `(race, className)`:
+tech-variants of the same class collapse into one node so the scene
+stays readable when a race fields a dozen tech levels of the same
+hull. The per-bucket label `<className>:<numLeft>` sums NumberLeft
+across the underlying groups; per-tech detail is available in the
+Reports view (Foreign Ship Classes / My Ship Types).
+
+Bucket order inside a cluster is **locked at battle start** by the
+initial ship count (`num` summed across tech variants, descending),
+together with mass, radius and local position. The static layout
+lives in `staticBucketsByRace`; the per-frame derivation
+`renderedByRace` overlays the live `NumberLeft` and drops buckets
+once they hit zero. The remaining buckets keep their slots in the
+cloud, so the cluster does not reshuffle when a class empties — the
+empty bucket simply disappears.
+
+Vogel positions are reassigned per rank by their inward distance
+toward the planet, so the rank-0 bucket (the largest by initial
+ship count) always sits at the most-inward spiral slot.
+
+When two races remain in battle the radial layout switches to the
+horizontal duel: race 0 at 9 o'clock, race 1 at 3 o'clock. This
+keeps both race labels clear of the SVG top edge and reads as the
+two sides facing off naturally.
+
+Circle radius scales with per-ship FullMass (Empty + Carrying via
+the per-ship `LoadQuantity`). The viewer resolves a
+`(race, className) → ShipClassRef` lookup from the surrounding
+`GameReport.localShipClass` + `otherShipClass` tables and runs it
+through the existing wasm bridge to `pkg/calc/ship.go`
+(`emptyMass` + `carryingMass` + `fullMass`). The radius is then
+`MIN_RADIUS + (MAX_RADIUS − MIN_RADIUS) × sqrt(mass / maxMassInBattle)`
+clamped to `[6, 24]` pixels — per-battle normalisation, so the
+heaviest ship in any given battle renders at the cap. Unknown class
+or invalid params fall back to MAX_RADIUS so the bucket stays
+visible.
+
+The current frame's shot is drawn as a thin line from the attacker's
+class circle to the defender's class circle. Colour:
+
+- red (`#ee3344`) when the action's `x === true` (the defender
+  ship was destroyed),
+- green (`#44dd66`) otherwise.
+
+Each frame redraws the line in isolation, so continuous playback
+produces the "shot-shot-shot" pulse the user wanted.
+
+## Playback controls
+
+`lib/battle-player/playback-controls.svelte` ships:
+
+| Control            | Effect                                                  |
+| ------------------ | ------------------------------------------------------- |
+| ⏮ rewind           | Stop, jump to frame 0                                   |
+| ◀︎◀︎ step back     | Stop, frame ← frame − 1                                 |
+| ▶︎ / ⏸ play        | Toggle continuous playback                              |
+| ▶︎▶︎ step forward  | Stop, frame ← frame + 1                                 |
+| `Nx` cycle speed   | Single button, cycles 1x → 2x → 4x → 6x → 1x; the label shows the current speed (400 / 200 / 100 / 67 ms per frame) |
+| `Log ▲▼` toggle    | Collapses / expands the always-visible text protocol so the user can give the scene the full viewer height |
+
+When the timeline is at its end and the user hits play, the frame
+counter wraps to 0 and continues. Step buttons disable themselves at
+their boundary.
+
+A drag-seek slider sits between the scene and the controls. Dragging
+pauses playback and lands `frameIndex` on the chosen shot — handy
+for jumping to the moment a particular race started losing ground.
+
+## Accessibility
+
+Below the scene the viewer renders a static `<ol>` text protocol —
+one line per action, formatted from `BattleReportGroup.race` and
+`BattleReportGroup.className`. The line for the current frame is
+highlighted so a non-visual reader can follow along by scrolling
+the log instead of watching the SVG. The list is always present
+and never hidden, satisfying the original Phase 27 acceptance "the
+same data is accessible as a static text log".
+
+Each log row is also a `<button>`: a click or Enter/Space jumps
+playback to that shot (pauses and seeks). The list auto-scrolls
+the current row into view as the timeline advances, so the user
+does not have to chase the highlight on long battles.
+
+## Playback details
+
+On play, the shot line + the defender circle's colour flash gate
+on a per-frame timer that blinks them off during the last 10 % of
+the frame's duration. Two consecutive shots from the same attacker
+on the same defender therefore look like two distinct pulses
+rather than one continuous line. On pause the line and flash
+stay drawn so the user can study the current shot.
+
+## Aggregated ship-class buckets
+
+Real legacy reports list the same `(race, className)` pair across
+several roster rows — different tech variants, ships pulled from
+multiple stacks or planets. The legacy-report parser
+([parser.go](../../tools/local-dev/legacy-report/parser.go))
+collapses those rows into a single `BattleReportGroup` keyed by
+`(race, className)` by SUMMING `Number` and `NumberLeft`; the
+engine's `TransformBattle`
+([battle_transform.go](../../game/internal/controller/battle_transform.go))
+applies the same merge keyed by `ShipClass.ID`, guarded by a
+processed-group set so the same source `groupId` is not summed
+twice across multiple protocol references.
+
+Without this aggregation only the last roster row's counts
+survived, and the protocol's destroy count against the class
+would dwarf the recorded initial count — KNNTS041 turn 41 planet
+\#7 had 7 separate `Nails:pup` rows totalling 1168 ships; the
+buggy parser stored only the last row's 88, so the 1082 destroys
+in the protocol looked like phantom hits past the empty bucket.
+After the fix both sides reconcile: 1168 initial − 86 survivors =
+1082 destroys.
+
+`buildFrames`
+([timeline.ts](../src/lib/battle-player/timeline.ts)) keeps a
+defence-in-depth clamp `if (left > 0)` on the destroy decrement so
+a malformed protocol never pushes a race below zero; in normal
+operation the clamp is a no-op because parser + engine already
+folded duplicate rows together.
+
+## Final-frame freeze
+
+When the last protocol action eliminates a race, the surviving
+side would otherwise reflow alone to the planet ring at the very
+last shot — visually jarring and uninformative. `displayFrame`
+freezes the layout-determining state (`remaining` and
+`activeRaceIds`) at the penultimate frame's values while keeping
+the final frame's `shotIndex` and `lastAction`, so the killing
+shot still renders as a line + flash against the picture the user
+saw a moment earlier.
+
+## Header + layout
+
+The viewer header carries three rows of chrome in a single line:
+the back-navigation buttons (`back to map` / `back to report`) on
+the left, a centred title — `Battle on planet <name> (<#number>)`,
+i18n key `game.battle.header_title` — and the frame counter on the
+right. Pulling navigation into the header frees the entire viewer
+area for the scene; the `.viewer` container has no `max-width` cap,
+so on wide monitors the scene scales up while the log keeps its
+internal 30 dvh scroll.
+
+## Height fit
+
+The viewer is pinned to the viewport: `.active-view` uses
+`calc(100dvh − 80px)` so the in-game-shell header + optional
+HistoryBanner do not push the scene below the fold. Inside the
+viewer, the scene grows (`flex: 1`), the scrubber + controls hold
+their natural height, and the log (when expanded) shrinks to a
+30 dvh ceiling with its own internal scroll, so the page itself
+never scrolls vertically. The 80 px allowance maps to the current
+Header + HistoryBanner total on desktop; mobile breakpoints reuse
+the same calc because dvh tracks the dynamic viewport.
+
+## Map markers
+
+`map/battle-markers.ts` emits two marker kinds per
+current-turn report. Both are wired into the binding's
+`hitLookup` so a click goes through the existing hit-test plumbing.
+
+### Battle marker — yellow cross
+
+For every `report.battles[i]` whose `planet` resolves to a visible
+planet, the marker emits two `LinePrim` lines through the opposite
+corners of the square circumscribed around the planet circle. The
+result is an X-shaped cross overlaid on the planet glyph.
+
+The stroke width is computed by `battleMarkerStrokeWidth(shots)`:
+1 shot → 1 px, 100 shots → 5 px, linearly interpolated in between
+(`width = 1 + (shots − 1) × 4 / 99`, clamped). A click on either
+line navigates to `/games/<id>/battle/<battleId>?turn=<turn>`.
+
+### Bombing marker — colored ring
+
+For every `report.bombings[i]`, the marker emits a single
+stroke-only `CirclePrim` slightly larger than the planet circle.
+Colour:
+
+- yellow (`#FFD400`) when `wiped: false`,
+- red (`#FF3030`) when `wiped: true`.
+
+A click on the ring navigates to `/games/<id>/report#report-bombings`
+and scrolls the matching `report-bombing-row` (by `data-planet`)
+into view. Bombing markers never open the Battle Viewer — the two
+domains stay separate.
+
+## Data source
+
+The Battle Viewer page (`lib/active-view/battle.svelte`) calls
+`api/battle-fetch.ts.fetchBattle(gameId, turn, battleId)`. The
+loader has two modes:
+
+- **Synthetic** — when `gameId` carries the
+  `synthetic-` prefix, the lookup is served from
+  `api/synthetic-battle.ts`. Vitest unit tests and Playwright e2e
+  tests register fixture battles via `registerSyntheticBattle`
+  before mounting the route.
+- **Production** — otherwise the loader issues
+  `GET /api/v1/user/games/{gameId}/battles/{turn}/{battleId}`
+  against the backend gateway route added in
+  `backend/internal/server/handlers_user_games.go.Battle`. The
+  gateway forwards verbatim to the engine's
+  `GET /api/v1/battle/:turn/:uuid`.
+
+## TODOs
+
+- Push event `game.battle.new` + toast → viewer link (deferred —
+  needs an engine emit-side change).
+- Richer ship-class visuals derived from the class's mass,
+  armament, shields. Current MVP uses a small circle plus
+  `<class>:<numLeft>` label.
+- Animated transitions when a race drops out and the survivors
+  re-distribute. Current implementation hard-jumps on the next
+  frame.

ui/docs/events.md

@@ -0,0 +1,118 @@
+# UI events stream (`api/events.svelte.ts`)
+
+This document describes how the SvelteKit frontend consumes the
+gateway's `SubscribeEvents` server-streaming RPC. The single
+authenticated session keeps **one** stream open through the
+`EventStream` singleton declared in `src/api/events.svelte.ts`; the
+root layout starts it once the session reaches `authenticated` and
+stops it on sign-out.
+
+## Why a single consumer
+
+Before Phase 24, the watcher in `lib/revocation-watcher.ts` opened a
+parallel stream just to observe session revocation. Phase 24 folds
+that watcher into `EventStream` so that:
+
+- there is only **one** SubscribeEvents connection per session
+  (avoids doubling the gateway hub load);
+- both clean end-of-stream on an authenticated session and an
+  `Unauthenticated` ConnectError funnel through one
+  `session.signOut("revoked")` call site;
+- per-event-type dispatch (turn-ready toasts, lobby/mail/battle
+  notifications later) shares the same verification path.
+
+## Lifecycle
+
+```
+SessionStore.status = "authenticated"
+    ↓ (root layout $effect)
+EventStream.start({ core, keypair, deviceSessionId, gatewayResponsePublicKey })
+    ↓
+loop: open SubscribeEvents → verify each frame → dispatch to handlers
+    ↓
+EventStream.stop()  (on logout, unmount, or session id change)
+```
+
+`start` is idempotent for the same session: re-calling while the
+stream is running is a no-op. The root layout detects a session id
+flip (re-login on the same tab) by storing the bound id and calling
+`stop()` + `start()` against the fresh credentials.
+
+## Frame handling
+
+Every `GatewayEvent` is verified before dispatch:
+
+1. `core.verifyPayloadHash(payloadBytes, payloadHash)` — the SHA-256
+   digest of `payloadBytes` must equal `payloadHash`. A mismatch is
+   treated as a forgery.
+2. `core.verifyEvent(gatewayResponsePublicKey, signature, fields)` —
+   Ed25519 verification using the canonical signing input defined in
+   `ui/core/canon/event.go` (mirrored by `gateway/authn/event.go`).
+3. On success the verified projection (`VerifiedEvent`) is passed to
+   every handler registered via `eventStream.on(eventType, handler)`.
+
+Any verification failure throws `SignatureError`, which falls into
+the same retry path as a transport error: the loop classifies it as
+transient, tears the stream down, and reconnects with full-jitter
+exponential backoff (base 1 s, ceiling 30 s, unbounded retries).
+
+## Connection status
+
+`EventStream.connectionStatus` is a Svelte rune with five values:
+
+- `idle` — stream not running.
+- `connecting` — `subscribeEvents()` issued, no frame received yet.
+- `connected` — first frame verified and dispatched, attempt counter
+  reset to zero.
+- `reconnecting` — transient failure, backoff in flight.
+- `offline` — `navigator.onLine === false` at the moment of failure.
+
+The header connection-state indicator planned in `PLAN.md`
+cross-cutting shell reads this rune; it is not part of Phase 24 but
+the rune is wired now so a later phase can add the dot without
+touching this module.
+
+## Revocation semantics
+
+Two paths lead to `session.signOut("revoked")`:
+
+- a `ConnectError` with code `Unauthenticated`: the gateway rejected
+  the stream credentials (revoked device session);
+- a clean end-of-stream while `session.status === "authenticated"`:
+  the gateway's documented `session_invalidation` signal closes the
+  stream once the device session flips to revoked.
+
+Any other error (network drop, gateway 5xx, transient close,
+signature failure) keeps the session alive and triggers backoff +
+reconnect.
+
+## Adding a new event type
+
+1. Register a handler from the consumer module:
+   ```ts
+   const off = eventStream.on("mail.received", (event) => {
+       // parse event.payloadBytes
+   });
+   onDestroy(off);
+   ```
+2. If the handler reads scoped data (per-game, per-route), register
+   from a layout that owns that scope and pass the gameId via a
+   closure. The handler should filter events whose payload does not
+   match its scope (see `routes/games/[id]/+layout.svelte` for the
+   `game.turn.ready` filter).
+3. The payload encoding is owned by the producer side: the
+   `game.turn.ready` event uses JSON `{game_id, turn}`. Document
+   the schema next to the producer (e.g. `backend/README.md` §10).
+
+## Tests
+
+- Unit (Vitest): `tests/events.test.ts` mocks the transport via
+  `createRouterTransport` and covers verified dispatch, type
+  filtering, bad-signature reconnect, `Unauthenticated` sign-out,
+  clean end-of-stream sign-out, and connection-status transitions.
+- E2E (Playwright): `tests/e2e/turn-ready.spec.ts` serves a signed
+  `game.turn.ready` frame through `page.route`, asserts the toast
+  surfaces, and verifies manual dismiss without advance. The
+  advance roundtrip (toast → click "view now" → fresh report) is
+  covered by Vitest at the store level because it is sensitive to
+  Playwright-side network ordering.

ui/docs/game-state.md

@@ -37,6 +37,10 @@ The store exposes:
 | `gameId`      | `string`                      | active game id                                       |
 | `status`      | `idle / loading / ready / error` | current lifecycle state                            |
 | `report`      | `GameReport \| null`          | latest decoded report, `null` until first fetch      |
+| `currentTurn` | `number`                      | server's authoritative current turn (live snapshot)  |
+| `viewedTurn`  | `number`                      | turn whose snapshot is in `report`; equals `currentTurn` in live mode |
+| `historyMode` | `boolean` (derived)           | true while `status === "ready"` and `viewedTurn < currentTurn` |
+| `pendingTurn` | `number \| null`              | latest server turn the user has not yet opened       |
 | `wrapMode`    | `torus / no-wrap`             | per-game preference, persisted via `Cache`           |
 | `error`       | `string \| null`              | localised error message when `status === "error"`    |
 
@@ -45,8 +49,15 @@ The store exposes:
 - Phase 11 surfaces only the planet subset of the report. Later
   phases extend `GameReport` and `decodeReport` as their slice of
   the wire lands (ships, fleets, sciences, routes, battles, mail).
-- Phase 26 wires history mode through `setTurn(turn)`. The store
-  already supports it; the navigator UI is what is missing.
+- Phase 26 splits `currentTurn` from the turn whose snapshot is
+  displayed (`viewedTurn`) and adds `viewTurn(turn)` /
+  `returnToCurrent()` for history navigation. The derived
+  `historyMode` rune flips automatically when `viewedTurn <
+  currentTurn`; the layout passes it to Phase 12's sidebar /
+  bottom-tabs wiring (which hides the order tab) and to
+  `OrderDraftStore.bindClient` (which gates `add` / `remove` /
+  `move`). See "History mode" below for the cache and refresh
+  rules.
 - Phase 24 replaces the tab-focus refresh with push-event-driven
   refreshes; the visibility listener stays as a fallback for
   background tabs that miss a push.
@@ -88,17 +99,59 @@ result can resolve back to a planet without an extra lookup table.
 
 ## Refresh discipline
 
-`refresh()` re-fetches the same turn snapshot. It is called by the
-`visibilitychange` handler when `document.visibilityState ===
-"visible"` and the store is already in `ready` state. The map view's
-mount effect skips a re-render when the new snapshot's turn matches
-the previously-mounted turn (and the wrap mode is unchanged), so a
-no-op refresh does not flicker the canvas.
+`refresh()` re-fetches the current-turn snapshot. It is called by
+the `visibilitychange` handler when `document.visibilityState ===
+"visible"` and the store is already in `ready` state. The map
+view's mount effect skips a re-render when the new snapshot's turn
+matches the previously-mounted turn (and the wrap mode is
+unchanged), so a no-op refresh does not flicker the canvas.
 
-`setTurn(turn)` is the entry point for Phase 26 history mode:
-calling it on a different turn loads that snapshot and the same
-mount effect re-creates the renderer with the new world.
+In history mode `refresh()` is a no-op — forcing a reload would
+silently bump the user back onto the current turn while they are
+intentionally viewing a past one. Push events (Phase 24) still
+deliver new-turn notifications asynchronously while the user
+explores history, so the pending-turn toast continues to work.
 
 `setWrapMode(mode)` writes to `Cache` and updates the rune; the
 map view's effect picks the change up and re-mounts the renderer
 with the new mode.
+
+## History mode
+
+Phase 26 lets the user step backward through the report timeline
+without losing the live snapshot. The store keeps two turn runes:
+
+- `currentTurn` — the server's authoritative latest. Only
+  `setGame` and `advanceToPending` write to it.
+- `viewedTurn` — the turn currently rendered. `viewTurn(N)` flips
+  this rune and the underlying `report` to `N` without touching
+  `currentTurn`. `returnToCurrent()` is a one-line wrapper that
+  navigates back to live.
+
+The derived `historyMode` rune (`status === "ready" && viewedTurn
+< currentTurn`) drives every history-aware consumer:
+
+- the layout passes it to `Sidebar` / `BottomTabs` so the order
+  tab vanishes (Phase 12 prop wiring);
+- the layout passes a `getHistoryMode` getter to
+  `OrderDraftStore.bindClient` so `add` / `remove` / `move` are
+  no-ops while the user is looking at a past turn;
+- `RenderedReportSource` returns the raw report (no order overlay)
+  because the draft is composed against the current turn;
+- the new `HistoryBanner` component renders the sticky "Viewing
+  turn N · read-only" strip when the flag is true.
+
+`last-viewed-turn` semantics keep their Phase 11 meaning: "the
+latest turn the user was caught up on". `loadTurn` only writes the
+cache row when called with `isCurrent === true` (i.e. when the
+load matches `currentTurn`). Historical excursions are therefore
+ephemeral: closing the tab and reopening the game resumes on the
+last caught-up turn, not on the last clicked one.
+
+Past-turn reports are cached in the `game-history` namespace
+(`{gameId}/turn/{N}` → `GameReport`). The cache is written by
+`loadTurn` on every successful historical fetch and read first by
+`viewTurn(N)` before falling back to the network. Past turns are
+immutable, so the cache has no TTL and no eviction in Phase 26.
+The current-turn snapshot is deliberately *not* cached — it is
+mutable until the next engine tick.

ui/docs/navigation.md

@@ -75,17 +75,46 @@ end-to-end command flow) can set it on navigation.
 
 The Order entry is hidden when the layout's `historyMode` flag is
 true. Phase 12 plumbs the flag end-to-end as a prop —
-`+layout.svelte` passes a constant `false` to `Sidebar`, which
+`+layout.svelte` forwards a derived value to `Sidebar`, which
 forwards `hideOrder` to its `TabBar`; the same flag goes to
 `BottomTabs` so the mobile `Order` button is also suppressed. A
 `?sidebar=order` URL seed that arrives while the flag is true falls
 back to `inspector`, and an `$effect` on the sidebar resets
 `activeTab` away from `order` if the flag flips on mid-session.
-Phase 26 introduces `lib/history-mode.ts` and replaces the constant
-with the live signal; the order draft survives the toggle because
+
+Phase 26 wires the flag to the live history signal owned by
+`GameStateStore`. The derivation lives directly in `+layout.svelte`
+(`const historyMode = $derived(gameState.historyMode)`) — no
+separate `lib/history-mode.ts` module ships, because the layout is
+the single consumer and the project's compactness rule rejects a
+one-line indirection. The order draft survives the toggle because
 `OrderDraftStore` lives one level above the sidebar in the layout
-hierarchy. See [`order-composer.md`](order-composer.md) for the
-draft-store side of the flow.
+hierarchy; the same `historyMode` derivation is also fed into
+`OrderDraftStore.bindClient` so inspector-driven mutations
+(`add` / `remove` / `move`) become no-ops while the user is
+viewing a past turn. See [`order-composer.md`](order-composer.md)
+for the draft-store side of the flow and
+[`game-state.md`](game-state.md) for the rune split between
+`currentTurn` and `viewedTurn`.
+
+## Header turn navigator and history banner
+
+The header replaces the Phase 11 inline `turn N` text with a
+`← Turn N →` triplet (`lib/header/turn-navigator.svelte`). The
+arrows step `viewedTurn` by ±1 (disabled at boundaries `0` and
+`currentTurn`); clicking the middle button opens an absolute
+popover (desktop) or a fixed full-width drawer (mobile, ≤ 767.98
+px) listing every turn from `currentTurn` down to `0`. Selecting
+the current-turn row routes through `gameState.returnToCurrent()`;
+any other row calls `gameState.viewTurn(N)`. The popover reuses
+`view-menu.svelte`'s outside-click / Escape pattern.
+
+`lib/header/history-banner.svelte` renders directly under the
+header whenever `gameState.historyMode === true`. It shows
+"Viewing turn {N} · read-only" with a "Return to current turn"
+button that delegates back to `gameState.returnToCurrent()`. Both
+the navigator and the banner read `gameState` through context, so
+the layout is the only place where the wiring lives.
 
 ## Layout breakpoints
 

ui/docs/order-composer.md

@@ -36,11 +36,18 @@ entry by `cmdId`. Successfully applied entries stay visible in
 the draft (the player keeps composing until turn cutoff);
 rejected entries stay until the player edits or removes them.
 
-Phase 25 is reserved for one extension on top of this: per-line
-sequencing if a future use case needs to submit commands
-individually rather than in one batch. The wire shape is already
-flexible enough — the response carries an array of results — so
-Phase 25 only changes the client-side iteration policy.
+Phase 25 layers a transport-level policy on top of this baseline
+without changing the batch semantics. The submit pipeline now
+goes through `OrderQueue` (see
+[`sync-protocol.md`](sync-protocol.md)): the queue holds the
+submit while the browser is offline, classifies
+`turn_already_closed` and `game_paused` server replies into
+matching banners on the order tab, and exits the loop on the
+sticky states so a stream of mutations does not re-elicit the
+same gateway reply. Recovery from a `conflict` or `paused`
+banner happens on the next `game.turn.ready` push frame via
+`OrderDraftStore.resetForNewTurn`, which clears the local draft
+and re-hydrates from the server for the new turn.
 
 ## Local-validation invariant
 
@@ -63,8 +70,10 @@ submit pipeline filters the draft to `valid` entries only — any
 
 ```text
 draft ──validate──▶ valid ──submit──▶ submitting ──ack──▶ applied
-   ╲                  │                                  ╲
-    ╲──validate──▶ invalid                                ╲──nack──▶ rejected
+   ╲                  │                          │       ╲
+    ╲──validate──▶ invalid                       │        ╲──nack──▶ rejected
+                                                 │
+                                                 ╲────turn_already_closed──▶ conflict
 ```
 
 Transitions:
@@ -76,6 +85,14 @@ Transitions:
   the draft and sends it to the gateway.
 - **`submitting → applied` / `submitting → rejected`**: the gateway
   responded; the entry is no longer in flight.
+- **`submitting → conflict`** (Phase 25): the gateway returned
+  `resultCode = "turn_already_closed"`. The order tab surfaces a
+  banner above the command list. Any subsequent mutation
+  re-validates the conflict row back to `valid` / `invalid`; a
+  matching `game.turn.ready` push frame triggers
+  `resetForNewTurn`, which wipes the draft entirely. See
+  [`sync-protocol.md`](sync-protocol.md) for the full state
+  table and recovery paths.
 
 Phase 14 lands the local validators (`draft → valid | invalid`),
 the submit pipeline (`valid → submitting → applied | rejected`),
@@ -283,13 +300,14 @@ order composer uses the namespace.
 
 ## History mode wiring
 
-Phase 26 introduces a global history-mode flag. The IA section
-specifies that the Order tab is hidden when history mode is active —
-the player is browsing a past turn snapshot, and composing commands
-against an immutable snapshot would be confusing.
+Phase 26 implements history mode: the user can step back through
+past turns and see the report as it was. The IA section specifies
+that the Order tab is hidden when history mode is active — the
+player is browsing an immutable snapshot, and composing commands
+against it would be confusing.
 
 Phase 12 wires the flag end-to-end as a prop. The layout owns the
-flag (a constant `false` until Phase 26) and passes it to:
+flag and passes it to:
 
 - `Sidebar` as `historyMode`. The sidebar forwards it to its
   `TabBar` as `hideOrder`. The Order entry is filtered out of the
@@ -300,10 +318,31 @@ flag (a constant `false` until Phase 26) and passes it to:
 - `BottomTabs` as `hideOrder`. The mobile bottom-tab `Order`
   button is suppressed when true.
 
+Phase 26 turns the constant into a derived value driven by
+`GameStateStore.historyMode` (`viewedTurn < currentTurn` while
+`status === "ready"`). The same getter is also passed into
+`OrderDraftStore.bindClient` as `getHistoryMode`, which short-
+circuits the `add` / `remove` / `move` mutations to a no-op while
+the flag is true. This makes every Phase 14–22 inspector affordance
+that calls `orderDraft.add(...)` inert in history mode without
+per-component edits — the gate lives in the one chokepoint that
+all callers go through. The conflict / paused banners and the
+in-flight sync pipeline are untouched: they describe state that
+exists independently of the user's current view.
+
 The store itself stays alive across history-mode round-trips so
-the draft survives. Phase 26 will replace the constant with the
-real signal from `lib/history-mode.ts` and exercise the toggle in
-its own test suite.
+the draft survives the toggle. The `RenderedReportSource` overlay
+(`lib/rendered-report.svelte.ts`) additionally short-circuits in
+history mode: when `gameState.historyMode === true` it returns
+the raw report so the map / inspector do not project pending
+renames composed for the *current* turn onto a *past* report.
+
+See [`game-state.md`](game-state.md) for the `viewTurn` /
+`returnToCurrent` API, the cache namespace
+(`game-history/{gameId}/turn/{N}`), and the visibility-refresh
+short-circuit; see [`navigation.md`](navigation.md) for the turn
+navigator and the read-only banner that surface history mode in
+the chrome.
 
 ## Testing
 

ui/docs/storage.md

@@ -112,11 +112,13 @@ wipes every namespace.
 
 Namespaces in current use:
 
-| Namespace       | Key                 | Value type       | Owner                       |
-|-----------------|---------------------|------------------|-----------------------------|
-| `session`       | `device-session-id` | `string`         | Phase 7+                    |
-| `game-prefs`    | `{gameId}/wrap-mode` | `WrapMode`      | Phase 11+ (`game-state.md`) |
-| `order-drafts`  | `{gameId}/draft`    | `OrderCommand[]` | Phase 12+ (`order-composer.md`) |
+| Namespace       | Key                            | Value type       | Owner                              |
+|-----------------|--------------------------------|------------------|------------------------------------|
+| `session`       | `device-session-id`            | `string`         | Phase 7+                           |
+| `game-prefs`    | `{gameId}/wrap-mode`           | `WrapMode`       | Phase 11+ (`game-state.md`)        |
+| `game-prefs`    | `{gameId}/last-viewed-turn`    | `number`         | Phase 11+ (`game-state.md`)        |
+| `order-drafts`  | `{gameId}/draft`               | `OrderCommand[]` | Phase 12+ (`order-composer.md`)    |
+| `game-history`  | `{gameId}/turn/{N}`            | `GameReport`     | Phase 26+ (`game-state.md`)        |
 
 Later phases will add more per-feature namespaces (fixtures, lobby
 snapshot, etc.). The contract is namespace-strings stay scoped to

ui/docs/sync-protocol.md

@@ -0,0 +1,217 @@
+# UI sync protocol
+
+Phase 25 wires the transport-level policy that keeps the local
+order draft consistent with the gateway across two failure modes
+that Phase 14 punted on: transient network outages and turn
+cutoffs the player did not anticipate. The wiring also reacts to
+admin-initiated game pauses signalled by the new `game.paused`
+push event.
+
+The contract lives at three layers:
+
+- **Backend** owns the turn-cutoff guard and the auto-pause on
+  generation failure (`backend/internal/runtime/scheduler.go`,
+  `backend/internal/lobby/runtime_hooks.go`,
+  `backend/internal/server/handlers_user_games.go`); see
+  `docs/FUNCTIONAL.md §6.3` for the user-visible spec.
+- **Gateway** translates backend's `httperr` envelope into the
+  `ExecuteCommandResponse` envelope without re-interpreting the
+  code; `turn_already_closed` and `game_paused` surface as
+  `resultCode` values verbatim.
+- **UI** detects those codes in
+  [`src/sync/order-queue.svelte.ts`](../frontend/src/sync/order-queue.svelte.ts)
+  and projects them onto the
+  [`OrderDraftStore`](../frontend/src/sync/order-draft.svelte.ts)
+  state machine consumed by
+  [`order-tab.svelte`](../frontend/src/lib/sidebar/order-tab.svelte).
+
+This document covers the UI side of the protocol — send-loop
+semantics, retry budgets, conflict UX, paused UX, and the
+recovery paths back to a normal `synced` state.
+
+## Send-loop semantics
+
+The order draft store no longer calls `submitOrder` directly. Every
+auto-sync attempt goes through `OrderQueue.send(submitFn)`, which
+acts as a thin policy gate:
+
+```text
+mutation ──▶ scheduleSync ──▶ runSync ──▶ queue.send(submitFn)
+                                                │
+                                                ▼
+                                         classify outcome:
+                                          - success
+                                          - rejected
+                                          - conflict
+                                          - paused
+                                          - offline
+                                          - failed
+```
+
+The classification is dispatched into the store:
+
+| outcome     | command status flip                | syncStatus | banner side-effect                        |
+| ----------- | ---------------------------------- | ---------- | ----------------------------------------- |
+| `success`   | per-command `applied` / `rejected` | `synced`   | none                                      |
+| `rejected`  | submitting → `rejected`            | `error`    | none (the row colour is enough)           |
+| `conflict`  | submitting → `conflict`            | `conflict` | `conflictBanner = { turn, code, message }` |
+| `paused`    | submitting → `valid`               | `paused`   | `pausedBanner = { reason, code, message }` |
+| `offline`   | submitting → `valid`               | `offline`  | none — the status bar carries the copy    |
+| `failed`    | submitting → `valid`               | `error`    | `syncError = reason`                      |
+
+Only one submit is in flight at a time. Mutations made during a
+flight set `pending = true` so the loop runs one more iteration
+with a fresh snapshot once the active call settles.
+
+## Offline detection and retry budget
+
+`OrderQueue.start` subscribes to the browser's `online` / `offline`
+events and primes `OrderQueue.online` from `navigator.onLine`. The
+queue intentionally treats offline as a fast-fail:
+
+- A `send()` invocation with `online === false` returns
+  `{kind: "offline"}` without invoking `submitFn`. The draft store
+  reverts every submitting row back to `valid` and parks the loop
+  with `syncStatus = "offline"`. No further sends fire until the
+  browser re-emits `online`.
+- When the browser flips back to `online`, the queue invokes the
+  `onOnline` callback supplied at `start()`. The draft store wires
+  this callback to `scheduleSync()` — exactly one new attempt per
+  online flip. The store's existing single-slot pending machinery
+  takes care of the rest (further mutations during that attempt
+  coalesce into one follow-up).
+
+There is no inline retry inside `OrderQueue.send`. The
+plan's "retry once on reconnect" budget is therefore literal:
+
+- offline ⇒ hold (no attempt)
+- next `online` event ⇒ one attempt
+- attempt succeeds ⇒ `syncStatus = "synced"`
+- attempt throws ⇒ `syncStatus = "error"` and the existing
+  manual-retry affordance in the order tab applies
+
+A throw mid-flight while `navigator.onLine` is still `true` is
+treated as a regular failure (`failed` outcome). A throw whose
+`onlineProbe` check returns `false` collapses into `offline`, so
+flaky connectivity does not get classified as a hard error.
+
+## Conflict UX — `turn_already_closed`
+
+When the gateway returns `resultCode = "turn_already_closed"` (or
+the per-error-body `code` matches it), the queue emits a
+`conflict` outcome. The store:
+
+1. Marks every command that was in `submitting` as `conflict` —
+   the matching row shows the new badge.
+2. Records `conflictBanner = { turn, code, message }`. `turn` is
+   read from the `getCurrentTurn` callback the layout supplied at
+   `bindClient` (the turn the player was composing for); it may be
+   `null` in tests that omit the callback, in which case the
+   banner falls back to a turn-less template.
+3. Sets `syncStatus = "conflict"`. The loop exits without firing
+   the `pending` follow-up — `scheduleSync` short-circuits while
+   the store is in conflict, so a flurry of keystrokes does not
+   re-elicit the same gateway reply.
+
+The banner clears on either of two signals:
+
+- **Any local mutation** (`add`, `remove`, `move`) calls
+  `clearConflictForMutation`, which drops the banner and
+  re-validates every `conflict`-marked command back through the
+  local validator. The mutation then auto-syncs as usual — likely
+  a fresh attempt against the new turn, often resulting in
+  `success`.
+- **A `game.turn.ready` push** arriving while the store is in
+  `conflict` triggers `resetForNewTurn`. The local draft is
+  wiped, `hydrateFromServer` pulls the new turn's empty order,
+  and the banner clears. Old commands for the prior turn become
+  history (read-only) and live on the server's `user.games.order`
+  for `?turn=N`.
+
+## Paused UX — `game_paused` / `game.paused`
+
+The paused-banner has two entry points:
+
+- **`Orders` handler reply with `code = "game_paused"`** — the
+  player attempted to submit while the game was paused. The
+  queue emits a `paused` outcome; the store reverts submitting
+  rows to `valid`, records `pausedBanner = { reason, code, message }`,
+  and locks `syncStatus = "paused"`.
+- **`game.paused` push frame** — lobby published the event when
+  it flipped the game to `paused` (see backend §6.5). The layout
+  subscribes via `eventStream.on("game.paused", ...)` and calls
+  `orderDraft.markPaused({ reason })`, which arrives at the same
+  state via a different path.
+
+While in `paused` the auto-sync loop refuses to fire (the
+`scheduleSync` early-exit). The store's `hydrateFromServer` also
+short-circuits if `syncStatus === "paused"` to avoid clobbering
+the banner with a fresh `synced` flip.
+
+Recovery is the same as conflict: a `game.turn.ready` push
+clears the pause via `resetForNewTurn`. The matching admin flow
+on the backend is an explicit `/resume` followed by a successful
+scheduler tick that emits the next turn.
+
+## Recovery via `resetForNewTurn`
+
+`resetForNewTurn` is the single entry point that wipes both
+banners and rebuilds the draft against a fresh turn:
+
+```ts
+async resetForNewTurn(opts: { client; turn }) {
+    this.commands = [];
+    this.statuses = {};
+    this.updatedAt = 0;
+    this.conflictBanner = null;
+    this.pausedBanner = null;
+    this.syncStatus = "idle";
+    this.syncError = null;
+    await this.persist();
+    await this.hydrateFromServer({ client, turn });
+}
+```
+
+The layout calls it from the `game.turn.ready` subscription
+whenever the prior `syncStatus` was either `conflict` or
+`paused`. A regular turn advance (no banner active) keeps the
+existing behaviour: `markPendingTurn` shows the toast and the
+player chooses when to navigate; the local draft survives the
+transition unchanged.
+
+## Test surface
+
+- **Vitest unit**:
+  [`tests/order-queue.test.ts`](../frontend/tests/order-queue.test.ts)
+  covers the queue's classification + online/offline plumbing in
+  isolation;
+  [`tests/order-draft.test.ts`](../frontend/tests/order-draft.test.ts)
+  covers the store's reaction to each outcome and the
+  `resetForNewTurn` / `markPaused` paths;
+  [`tests/order-tab.test.ts`](../frontend/tests/order-tab.test.ts)
+  asserts the banner DOM;
+  [`tests/events.test.ts`](../frontend/tests/events.test.ts)
+  pins the `game.paused` dispatch.
+- **Playwright e2e**:
+  [`tests/e2e/order-sync.spec.ts`](../frontend/tests/e2e/order-sync.spec.ts)
+  drives the order tab through the conflict and paused-push
+  scenarios with mocked gateway and signed-event frames.
+
+The offline-online round-trip is covered at the Vitest level
+because Playwright's `context.setOffline(true)` is a coarse
+network mute that conflicts with the dev-server bootstrap and
+the in-test fixture key wiring; the store-level test uses
+injected `onlineProbe` / `addEventListener` to drive the same
+state machine deterministically.
+
+## Known follow-ups
+
+- Admin resume currently produces a `running → paused → running`
+  status flip on the lobby side without an explicit push event.
+  The UI relies on the next `game.turn.ready` for recovery; a
+  dedicated `game.resumed` event would let the banner clear
+  immediately without waiting for the next cron tick. Not part
+  of this phase.
+- The conflict banner shows the player-facing template
+  unmodified; a future revision may interpolate the explicit
+  cutoff timestamp once the server adds it to the error body.

ui/frontend/src/api/battle-fetch.ts

@@ -0,0 +1,88 @@
+// Battle-report fetcher used by the Battle Viewer page.
+//
+// Phase 27 ships the BattleViewer as a logically isolated component
+// that accepts a `BattleReport` matching `pkg/model/report/battle.go`.
+// This module owns the type mirror and a single `fetchBattle` entry
+// point. In synthetic mode (development & e2e fixtures), the loader
+// falls back to a local fixture so the UI tests don't depend on a
+// running engine; otherwise it issues a real `GET` against the
+// backend gateway route added in Phase 27 step 3.
+
+import { isSyntheticGameId } from "./synthetic-report";
+import { lookupSyntheticBattle } from "./synthetic-battle";
+
+/**
+ * BattleReport is the wire shape returned by the engine endpoint
+ * `GET /api/v1/battle/:turn/:uuid` and forwarded by the backend
+ * gateway as `GET /api/v1/user/games/{game_id}/battles/{turn}/{battle_id}`.
+ * Fields mirror `pkg/model/report/battle.go`.
+ */
+export interface BattleReport {
+	id: string;
+	planet: number;
+	planetName: string;
+	races: Record<string, string>;
+	ships: Record<string, BattleReportGroup>;
+	protocol: BattleActionReport[];
+}
+
+export interface BattleReportGroup {
+	race: string;
+	className: string;
+	tech: Record<string, number>;
+	num: number;
+	numLeft: number;
+	loadType: string;
+	loadQuantity: number;
+	inBattle: boolean;
+}
+
+export interface BattleActionReport {
+	a: number;
+	sa: number;
+	d: number;
+	sd: number;
+	x: boolean;
+}
+
+export class BattleFetchError extends Error {
+	constructor(public readonly status: number, message: string) {
+		super(message);
+		this.name = "BattleFetchError";
+	}
+}
+
+/**
+ * fetchBattle returns the `BattleReport` for the supplied game, turn,
+ * and battle id. In synthetic-report mode (DEV / e2e) the lookup is
+ * served from `synthetic-battle.ts`; otherwise the function calls the
+ * backend gateway route. Throws `BattleFetchError` with the upstream
+ * status on validation or transport failure.
+ */
+export async function fetchBattle(
+	gameId: string,
+	turn: number,
+	battleId: string,
+): Promise<BattleReport> {
+	if (isSyntheticGameId(gameId)) {
+		const fixture = lookupSyntheticBattle(battleId);
+		if (fixture === null) {
+			throw new BattleFetchError(404, "battle not found");
+		}
+		return fixture;
+	}
+	const path = `/api/v1/user/games/${encodeURIComponent(gameId)}/battles/${turn}/${encodeURIComponent(battleId)}`;
+	const response = await fetch(path, {
+		headers: { Accept: "application/json" },
+	});
+	if (response.status === 404) {
+		throw new BattleFetchError(404, "battle not found");
+	}
+	if (!response.ok) {
+		throw new BattleFetchError(
+			response.status,
+			`battle fetch failed: ${response.status}`,
+		);
+	}
+	return (await response.json()) as BattleReport;
+}

ui/frontend/src/api/events.svelte.ts

@@ -0,0 +1,376 @@
+// `EventStream` is the single SubscribeEvents consumer for the
+// authenticated UI session. It opens one server-streaming RPC against
+// the gateway, verifies every incoming event (payload-hash +
+// Ed25519 signature) through `ui/core`, dispatches verified events to
+// type-keyed handlers, and reconnects with full-jitter exponential
+// backoff on transient failure.
+//
+// Phase 24 introduces this module in place of `revocation-watcher.ts`.
+// The watcher's revocation semantics are absorbed: a clean
+// end-of-stream while the session is authenticated, or an
+// `Unauthenticated` ConnectError, both call `session.signOut("revoked")`.
+// Per-event-type dispatch (turn-ready toasts in this phase; battle and
+// mail toasts in later phases) is registered through `on(eventType,
+// handler)`.
+//
+// The store exposes `connectionStatus` as a Svelte rune so the
+// connection-state indicator in the shell header (see PLAN.md
+// cross-cutting shell) can subscribe without ceremony. The indicator
+// itself is not part of Phase 24, but the rune is wired here so the
+// next phase that adds the dot can read it directly.
+
+import { create } from "@bufbuild/protobuf";
+import { ConnectError } from "@connectrpc/connect";
+import type { Core } from "../platform/core/index";
+import type { DeviceKeypair } from "../platform/store/index";
+import {
+	GatewayEventSchema,
+	SubscribeEventsRequestSchema,
+	type GatewayEvent,
+} from "../proto/galaxy/gateway/v1/edge_gateway_pb";
+import { GATEWAY_BASE_URL } from "../lib/env";
+import { session } from "../lib/session-store.svelte";
+import { createEdgeGatewayClient, type EdgeGatewayClient } from "./connect";
+
+const PROTOCOL_VERSION = "v1";
+const SUBSCRIBE_MESSAGE_TYPE = "gateway.subscribe";
+
+// Connect error code numerical values used by the watcher. The full
+// enum lives in `@connectrpc/connect` but importing the runtime enum
+// would pull a large surface into this small module.
+const CONNECT_CODE_CANCELED = 1;
+const CONNECT_CODE_UNAUTHENTICATED = 16;
+
+const BACKOFF_BASE_MS = 1_000;
+const BACKOFF_MAX_MS = 30_000;
+
+/**
+ * VerifiedEvent is the verified projection of a `GatewayEvent` handed
+ * to user handlers. The signature and payload-hash fields are dropped
+ * because verification has already succeeded; consumers only need the
+ * envelope plus the opaque payload bytes.
+ */
+export interface VerifiedEvent {
+	eventType: string;
+	eventId: string;
+	timestampMs: bigint;
+	requestId: string;
+	traceId: string;
+	payloadBytes: Uint8Array;
+}
+
+export type EventHandler = (event: VerifiedEvent) => void;
+
+export type ConnectionStatus =
+	| "idle"
+	| "connecting"
+	| "connected"
+	| "reconnecting"
+	| "offline";
+
+/**
+ * EventStreamStartOptions carries the live primitives the stream
+ * consumer cannot resolve by itself. Production code reads `core`,
+ * `keypair`, and `deviceSessionId` from the session store and the
+ * gateway public key from `lib/env`; tests inject a fake
+ * `EdgeGatewayClient` and deterministic `sleep`/`random` to drive
+ * backoff in fake-timer mode.
+ */
+export interface EventStreamStartOptions {
+	core: Core;
+	keypair: DeviceKeypair;
+	deviceSessionId: string;
+	gatewayResponsePublicKey: Uint8Array;
+	/** Custom transport client. Defaults to `createEdgeGatewayClient(GATEWAY_BASE_URL)`. */
+	client?: EdgeGatewayClient;
+	/** Sleep hook for tests; defaults to a real-time `setTimeout`. */
+	sleep?: (ms: number) => Promise<void>;
+	/** Random source for full-jitter backoff; defaults to `Math.random`. */
+	random?: () => number;
+	/** Function reporting `navigator.onLine`; defaults to the browser global. */
+	onlineProbe?: () => boolean;
+}
+
+/**
+ * SignatureError marks a verification failure (payload-hash mismatch
+ * or invalid Ed25519 signature). The stream loop classifies it as a
+ * forgery and reconnects through the same backoff path used for
+ * transient transport errors.
+ */
+export class SignatureError extends Error {
+	constructor(message: string) {
+		super(message);
+		this.name = "SignatureError";
+	}
+}
+
+export class EventStream {
+	connectionStatus: ConnectionStatus = $state("idle");
+
+	private handlers = new Map<string, Set<EventHandler>>();
+	private controller: AbortController | null = null;
+	private running = false;
+
+	/**
+	 * on registers a handler for a specific event type. Returns a
+	 * disposer that removes the handler. Multiple handlers per type
+	 * are supported so future phases (battle, mail) can subscribe
+	 * alongside turn-ready without coordination.
+	 */
+	on(eventType: string, handler: EventHandler): () => void {
+		let bucket = this.handlers.get(eventType);
+		if (bucket === undefined) {
+			bucket = new Set();
+			this.handlers.set(eventType, bucket);
+		}
+		bucket.add(handler);
+		return () => {
+			const current = this.handlers.get(eventType);
+			if (current === undefined) {
+				return;
+			}
+			current.delete(handler);
+			if (current.size === 0) {
+				this.handlers.delete(eventType);
+			}
+		};
+	}
+
+	/**
+	 * start opens the stream. Calling start while the stream is
+	 * already running is a no-op so the root layout's `$effect`-based
+	 * lifecycle stays idempotent across re-renders.
+	 */
+	start(opts: EventStreamStartOptions): void {
+		if (this.running) {
+			return;
+		}
+		this.running = true;
+		this.controller = new AbortController();
+		void this.run(opts, this.controller.signal);
+	}
+
+	/**
+	 * stop tears down the stream. Used by the root layout on logout
+	 * or unmount. Re-calling start after stop opens a fresh stream.
+	 */
+	stop(): void {
+		this.running = false;
+		if (this.controller !== null) {
+			this.controller.abort();
+			this.controller = null;
+		}
+		this.connectionStatus = "idle";
+	}
+
+	/**
+	 * resetForTests is used by the Vitest harness to forget all
+	 * handlers and force the rune back to `idle` between cases.
+	 */
+	resetForTests(): void {
+		this.stop();
+		this.handlers.clear();
+	}
+
+	private async run(
+		opts: EventStreamStartOptions,
+		signal: AbortSignal,
+	): Promise<void> {
+		const sleep = opts.sleep ?? defaultSleep;
+		const random = opts.random ?? Math.random;
+		const onlineProbe = opts.onlineProbe ?? defaultOnlineProbe;
+		const client = opts.client ?? createEdgeGatewayClient(GATEWAY_BASE_URL);
+
+		let attempt = 0;
+		while (!signal.aborted && this.running) {
+			this.connectionStatus = "connecting";
+			let stream: AsyncIterable<GatewayEvent>;
+			try {
+				stream = await openStream(client, opts, signal);
+			} catch (err) {
+				if (signal.aborted) {
+					return;
+				}
+				if (handleAuthenticationError(err)) {
+					return;
+				}
+				this.connectionStatus = onlineProbe() ? "reconnecting" : "offline";
+				await sleep(backoffDelay(attempt, random));
+				attempt += 1;
+				continue;
+			}
+
+			let firstEventSeen = false;
+			let terminated = false;
+			try {
+				for await (const event of stream) {
+					if (signal.aborted) {
+						return;
+					}
+					this.verifyEvent(event, opts);
+					if (!firstEventSeen) {
+						firstEventSeen = true;
+						this.connectionStatus = "connected";
+						attempt = 0;
+					}
+					this.dispatch(event);
+				}
+				terminated = true;
+			} catch (err) {
+				if (signal.aborted) {
+					return;
+				}
+				if (handleAuthenticationError(err)) {
+					return;
+				}
+				this.connectionStatus = onlineProbe() ? "reconnecting" : "offline";
+				await sleep(backoffDelay(attempt, random));
+				attempt += 1;
+				continue;
+			}
+
+			if (terminated) {
+				// Clean end-of-stream on an authenticated session is the
+				// gateway's documented session-invalidation signal.
+				if (session.status === "authenticated") {
+					await session.signOut("revoked");
+					return;
+				}
+				this.connectionStatus = "idle";
+				return;
+			}
+		}
+	}
+
+	private verifyEvent(event: GatewayEvent, opts: EventStreamStartOptions): void {
+		if (!opts.core.verifyPayloadHash(event.payloadBytes, event.payloadHash)) {
+			throw new SignatureError("event payload_hash mismatch");
+		}
+		const ok = opts.core.verifyEvent(
+			opts.gatewayResponsePublicKey,
+			event.signature,
+			{
+				eventType: event.eventType,
+				eventId: event.eventId,
+				timestampMs: event.timestampMs,
+				requestId: event.requestId,
+				traceId: event.traceId,
+				payloadHash: event.payloadHash,
+			},
+		);
+		if (!ok) {
+			throw new SignatureError("event signature verification failed");
+		}
+	}
+
+	private dispatch(event: GatewayEvent): void {
+		const bucket = this.handlers.get(event.eventType);
+		if (bucket === undefined || bucket.size === 0) {
+			return;
+		}
+		const projection: VerifiedEvent = {
+			eventType: event.eventType,
+			eventId: event.eventId,
+			timestampMs: event.timestampMs,
+			requestId: event.requestId,
+			traceId: event.traceId,
+			payloadBytes: event.payloadBytes,
+		};
+		for (const handler of [...bucket]) {
+			try {
+				handler(projection);
+			} catch (err) {
+				console.info("events: handler threw", event.eventType, err);
+			}
+		}
+	}
+}
+
+async function openStream(
+	client: EdgeGatewayClient,
+	opts: EventStreamStartOptions,
+	signal: AbortSignal,
+): Promise<AsyncIterable<GatewayEvent>> {
+	const requestId = newRequestId();
+	const timestampMs = BigInt(Date.now());
+	const emptyPayload = new Uint8Array();
+	const payloadHash = await sha256(emptyPayload);
+	const canonical = opts.core.signRequest({
+		protocolVersion: PROTOCOL_VERSION,
+		deviceSessionId: opts.deviceSessionId,
+		messageType: SUBSCRIBE_MESSAGE_TYPE,
+		timestampMs,
+		requestId,
+		payloadHash,
+	});
+	const signature = await opts.keypair.sign(canonical);
+	const request = create(SubscribeEventsRequestSchema, {
+		protocolVersion: PROTOCOL_VERSION,
+		deviceSessionId: opts.deviceSessionId,
+		messageType: SUBSCRIBE_MESSAGE_TYPE,
+		timestampMs,
+		requestId,
+		payloadHash,
+		signature,
+		payloadBytes: emptyPayload,
+	});
+	return client.subscribeEvents(request, { signal });
+}
+
+function handleAuthenticationError(err: unknown): boolean {
+	if (!(err instanceof ConnectError)) {
+		return false;
+	}
+	if (err.code === CONNECT_CODE_CANCELED) {
+		return true;
+	}
+	if (err.code === CONNECT_CODE_UNAUTHENTICATED) {
+		void session.signOut("revoked");
+		return true;
+	}
+	return false;
+}
+
+function backoffDelay(attempt: number, random: () => number): number {
+	const cap = Math.min(BACKOFF_MAX_MS, BACKOFF_BASE_MS * 2 ** attempt);
+	return Math.floor(random() * cap);
+}
+
+function defaultSleep(ms: number): Promise<void> {
+	return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+function defaultOnlineProbe(): boolean {
+	if (typeof navigator === "undefined") {
+		return true;
+	}
+	return navigator.onLine !== false;
+}
+
+async function sha256(payload: Uint8Array): Promise<Uint8Array> {
+	const digest = await crypto.subtle.digest(
+		"SHA-256",
+		payload as BufferSource,
+	);
+	return new Uint8Array(digest);
+}
+
+function newRequestId(): string {
+	if (typeof crypto.randomUUID === "function") {
+		return crypto.randomUUID();
+	}
+	const buf = new Uint8Array(16);
+	crypto.getRandomValues(buf);
+	let hex = "";
+	for (let i = 0; i < buf.length; i++) {
+		hex += buf[i]!.toString(16).padStart(2, "0");
+	}
+	return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20, 32)}`;
+}
+
+/**
+ * eventStream is the singleton stream consumer the root layout starts
+ * once the session becomes authenticated and stops on logout. Tests
+ * call `resetForTests()` between cases.
+ */
+export const eventStream = new EventStream();

ui/frontend/src/api/game-state.ts

@@ -382,6 +382,18 @@ export interface ReportBombing {
  * mirrors the producing planet's free industry. Stable order: sorted
  * by `(planetNumber, class)`.
  */
+/**
+ * ReportBattle is one battle summary in the current turn. Carries the
+ * battle UUID, planet number, and shot count — enough to render a
+ * battle marker on the map and to link into the Battle Viewer without
+ * fetching the full BattleReport.
+ */
+export interface ReportBattle {
+	id: string;
+	planet: number;
+	shots: number;
+}
+
 export interface ReportShipProduction {
 	planetNumber: number;
 	class: string;
@@ -524,11 +536,17 @@ export interface GameReport {
 	 */
 	otherShipClass: ReportOtherShipClass[];
 	/**
-	 * battleIds is the list of battle UUIDs the engine recorded for
-	 * the current turn. Phase 23 renders them as inactive
-	 * monospace identifiers; Phase 27 will turn them into navigation
-	 * targets once the battle viewer lands. Empty when no battles
-	 * occurred last turn.
+	 * battles is the list of battle summaries the engine recorded for
+	 * the current turn. Each entry carries the battle UUID, the planet
+	 * it happened on, and the number of shots exchanged. The Reports
+	 * View uses `id` to link into the Battle Viewer; the map renderer
+	 * uses `planet` to locate the marker and `shots` to scale its
+	 * stroke. Empty when no battles occurred last turn.
+	 */
+	battles: ReportBattle[];
+	/**
+	 * battleIds is a convenience derived list of UUIDs from `battles`,
+	 * preserved for legacy callers (Phase 23 report section, fixtures).
 	 */
 	battleIds: string[];
 	/**
@@ -700,7 +718,8 @@ function decodeReport(report: Report): GameReport {
 	const localFleets = decodeLocalFleets(report);
 	const otherScience = decodeOtherScience(report);
 	const otherShipClass = decodeOtherShipClass(report);
-	const battleIds = decodeBattleIds(report);
+	const battles = decodeBattles(report);
+	const battleIds = battles.map((b) => b.id);
 	const bombings = decodeBombings(report);
 	const shipProductions = decodeShipProductions(report);
 
@@ -730,6 +749,7 @@ function decodeReport(report: Report): GameReport {
 		players,
 		otherScience,
 		otherShipClass,
+		battles,
 		battleIds,
 		bombings,
 		shipProductions,
@@ -1153,13 +1173,18 @@ function decodeOtherShipClass(report: Report): ReportOtherShipClass[] {
 	return out;
 }
 
-function decodeBattleIds(report: Report): string[] {
-	const out: string[] = [];
+function decodeBattles(report: Report): ReportBattle[] {
+	const out: ReportBattle[] = [];
 	for (let i = 0; i < report.battleLength(); i++) {
-		const uuid = report.battle(i);
-		const value = uuidStringFromFB(uuid);
-		if (value === null) continue;
-		out.push(value);
+		const summary = report.battle(i);
+		if (summary === null) continue;
+		const id = uuidStringFromFB(summary.id());
+		if (id === null) continue;
+		out.push({
+			id,
+			planet: Number(summary.planet()),
+			shots: Number(summary.shots()),
+		});
 	}
 	return out;
 }
@@ -1439,6 +1464,7 @@ export function applyOrderOverlay(
 		players: report.players ?? [],
 		otherScience: report.otherScience ?? [],
 		otherShipClass: report.otherShipClass ?? [],
+		battles: report.battles ?? [],
 		battleIds: report.battleIds ?? [],
 		bombings: report.bombings ?? [],
 		shipProductions: report.shipProductions ?? [],

ui/frontend/src/api/synthetic-battle.ts

@@ -0,0 +1,37 @@
+// Synthetic battle reports for DEV / e2e mode.
+//
+// Mirrors the shape of `pkg/model/report/battle.go` so the
+// BattleViewer can be exercised without a running engine. Fixtures
+// are registered by battle UUID; the synthetic-report loader fills
+// the report's `battles[]` with these same UUIDs so the report ↔
+// battle link is consistent.
+
+import type { BattleReport } from "./battle-fetch";
+
+const SYNTHETIC_BATTLES = new Map<string, BattleReport>();
+
+/**
+ * registerSyntheticBattle adds a fixture battle to the in-memory map
+ * keyed by its `id`. Used by the synthetic-report DEV loader and by
+ * Vitest unit tests that need a deterministic BattleReport without a
+ * live engine.
+ */
+export function registerSyntheticBattle(report: BattleReport): void {
+	SYNTHETIC_BATTLES.set(report.id, report);
+}
+
+/**
+ * lookupSyntheticBattle returns the fixture stored under `battleId`,
+ * or `null` if nothing was registered (mirrors the engine's 404).
+ */
+export function lookupSyntheticBattle(battleId: string): BattleReport | null {
+	return SYNTHETIC_BATTLES.get(battleId) ?? null;
+}
+
+/**
+ * resetSyntheticBattles clears every registered fixture. Test
+ * harnesses call this between cases to avoid bleed-through.
+ */
+export function resetSyntheticBattles(): void {
+	SYNTHETIC_BATTLES.clear();
+}

ui/frontend/src/api/synthetic-report.ts

@@ -39,6 +39,8 @@ import type {
 } from "./game-state";
 import type { CargoLoadType, Relation } from "../sync/order-types";
 import { isCargoLoadType, isRelation } from "../sync/order-types";
+import type { BattleReport } from "./battle-fetch";
+import { registerSyntheticBattle } from "./synthetic-battle";
 
 export const SYNTHETIC_GAME_ID_PREFIX = "synthetic-";
 
@@ -59,18 +61,71 @@ export class SyntheticReportError extends Error {
  * loadSyntheticReportFromJSON validates the passed payload, decodes
  * it into a `GameReport`, registers it in the in-memory map under a
  * fresh `synthetic-<uuid>` id, and returns both the id and the
- * decoded report. Throws `SyntheticReportError` for malformed input.
+ * decoded report.
+ *
+ * Accepts two on-disk shapes:
+ *
+ *   1. Envelope (Phase 27 legacy-report CLI):
+ *      `{ "version": 1, "report": <Report>, "battles": { <uuid>: <BattleReport> } }`
+ *      — battles are forwarded to `registerSyntheticBattle` so the
+ *      Battle Viewer can resolve them offline.
+ *   2. Bare Report (pre-envelope synthetic JSON files) — same as
+ *      before; battle UUIDs in the report can still be clicked, but
+ *      the Viewer page will show "battle not found" because no
+ *      fixture was registered.
+ *
+ * Throws `SyntheticReportError` for malformed input in either shape.
  */
 export function loadSyntheticReportFromJSON(json: unknown): {
 	gameId: string;
 	report: GameReport;
 } {
-	const report = decodeSyntheticReport(json);
+	const { reportPayload, battles } = extractEnvelope(json);
+	const report = decodeSyntheticReport(reportPayload);
+	for (const battle of battles) {
+		registerSyntheticBattle(battle);
+	}
 	const gameId = SYNTHETIC_GAME_ID_PREFIX + crypto.randomUUID();
 	SYNTHETIC_REPORTS.set(gameId, report);
 	return { gameId, report };
 }
 
+interface SyntheticEnvelope {
+	version?: number;
+	report?: unknown;
+	battles?: Record<string, BattleReport>;
+}
+
+/**
+ * extractEnvelope distinguishes the v1 envelope shape from a bare
+ * Report payload. The envelope check is `version === 1` to leave room
+ * for future format bumps and to avoid mistaking a bare Report whose
+ * top-level fields happen to include `report`/`battles` (none do
+ * today) for an envelope.
+ */
+function extractEnvelope(json: unknown): {
+	reportPayload: unknown;
+	battles: BattleReport[];
+} {
+	if (typeof json !== "object" || json === null) {
+		// Defer the error to `decodeSyntheticReport`; it already
+		// raises a `SyntheticReportError` with the right message.
+		return { reportPayload: json, battles: [] };
+	}
+	const env = json as SyntheticEnvelope;
+	if (env.version === 1 && env.report !== undefined) {
+		const battlesMap = env.battles ?? {};
+		const battles: BattleReport[] = [];
+		for (const value of Object.values(battlesMap)) {
+			if (value && typeof value === "object") {
+				battles.push(value);
+			}
+		}
+		return { reportPayload: env.report, battles };
+	}
+	return { reportPayload: json, battles: [] };
+}
+
 /** getSyntheticReport returns the report registered under `gameId`,
  * or `undefined` if the entry was lost (e.g. page reload). */
 export function getSyntheticReport(gameId: string): GameReport | undefined {
@@ -173,6 +228,12 @@ interface SyntheticOtherShipClass extends SyntheticShipClass {
 	mass?: number;
 }
 
+interface SyntheticBattle {
+	id?: string;
+	planet?: number;
+	shots?: number;
+}
+
 interface SyntheticBombing {
 	planet?: number; // wire field "number"
 	planetName?: string; // wire field "planetName"
@@ -219,7 +280,7 @@ interface SyntheticReportRoot {
 	incomingGroup?: SyntheticIncomingGroup[];
 	unidentifiedGroup?: SyntheticUnidentifiedGroup[];
 	localFleet?: SyntheticLocalFleet[];
-	battle?: string[];
+	battle?: SyntheticBattle[];
 	bombing?: SyntheticBombing[];
 	shipProduction?: SyntheticShipProductionRow[];
 }
@@ -357,9 +418,17 @@ function decodeSyntheticReport(json: unknown): GameReport {
 		return a.name.localeCompare(b.name);
 	});
 
-	const battleIds: string[] = (root.battle ?? []).filter(
-		(v): v is string => typeof v === "string" && v !== "",
-	);
+	const battles = (root.battle ?? [])
+		.filter(
+			(v): v is SyntheticBattle =>
+				typeof v === "object" && v !== null && typeof v.id === "string" && v.id !== "",
+		)
+		.map((b) => ({
+			id: b.id as string,
+			planet: numOr0(b.planet),
+			shots: numOr0(b.shots),
+		}));
+	const battleIds = battles.map((b) => b.id);
 
 	const bombings: ReportBombing[] = (root.bombing ?? []).map((b) => ({
 		planetNumber: numOr0(b.planet),
@@ -419,6 +488,7 @@ function decodeSyntheticReport(json: unknown): GameReport {
 		players: collectPlayersFromSynthetic(root, race),
 		otherScience,
 		otherShipClass,
+		battles,
 		battleIds,
 		bombings,
 		shipProductions,

ui/frontend/src/app.html

@@ -5,6 +5,12 @@
 		<link rel="icon" href="%sveltekit.assets%/favicon.svg" />
 		<meta name="viewport" content="width=device-width, initial-scale=1" />
 		<title>Galaxy</title>
+		<style>
+			html,
+			body {
+				margin: 0;
+			}
+		</style>
 		%sveltekit.head%
 	</head>
 	<body data-sveltekit-preload-data="hover">

ui/frontend/src/lib/active-view/battle.svelte

@@ -1,30 +1,172 @@
 <!--
-Phase 10 stub for the battle-log active view. Phase 27 wires the real
-battle viewer.
+Phase 27 — active-view wrapper around the BattleViewer. Loads the
+BattleReport for the supplied `gameId`/`turn`/`battleId` and either
+shows the radial playback (BattleViewer), a loading skeleton, or a
+not-found state.
+
+This wrapper also bridges the surrounding GameReport's ship-class
+tables into a `(race, className) → ShipClassRef` lookup the viewer
+needs to size class circles by ship mass. The back-navigation
+buttons (`back to map` / `back to report`) live INSIDE the viewer
+header now — we just hand the routes down as callbacks so the
+viewer keeps its prop-driven contract.
 -->
 <script lang="ts">
-	import { i18n } from "$lib/i18n/index.svelte";
+	import { getContext } from "svelte";
+	import { goto } from "$app/navigation";
 
-	type Props = { battleId: string };
-	let { battleId }: Props = $props();
+	import {
+		BattleFetchError,
+		fetchBattle,
+		type BattleReport,
+	} from "../../api/battle-fetch";
+	import { i18n } from "$lib/i18n/index.svelte";
+	import {
+		RENDERED_REPORT_CONTEXT_KEY,
+		type RenderedReportSource,
+	} from "$lib/rendered-report.svelte";
+	import {
+		MapShipClassLookup,
+		type ShipClassLookup,
+		type ShipClassRef,
+	} from "../battle-player/mass";
+
+	import BattleViewer from "../battle-player/battle-viewer.svelte";
+
+	let {
+		gameId,
+		turn,
+		battleId,
+	}: {
+		gameId: string;
+		turn: number;
+		battleId: string;
+	} = $props();
+
+	const rendered = getContext<RenderedReportSource | undefined>(
+		RENDERED_REPORT_CONTEXT_KEY,
+	);
+
+	const shipClassLookup = $derived.by<ShipClassLookup>(() => {
+		const map = new Map<string, ShipClassRef>();
+		const report = rendered?.report;
+		if (report) {
+			for (const cls of report.localShipClass) {
+				map.set(`${report.race}::${cls.name}`, {
+					drive: cls.drive,
+					weapons: cls.weapons,
+					armament: cls.armament,
+					shields: cls.shields,
+					cargo: cls.cargo,
+				});
+			}
+			for (const cls of report.otherShipClass) {
+				map.set(`${cls.race}::${cls.name}`, {
+					drive: cls.drive,
+					weapons: cls.weapons,
+					armament: cls.armament,
+					shields: cls.shields,
+					cargo: cls.cargo,
+				});
+			}
+		}
+		return new MapShipClassLookup(map);
+	});
+
+	let state = $state<
+		| { kind: "loading" }
+		| { kind: "ready"; report: BattleReport }
+		| { kind: "not_found" }
+		| { kind: "error"; message: string }
+	>({ kind: "loading" });
+
+	$effect(() => {
+		if (!battleId) {
+			state = { kind: "not_found" };
+			return;
+		}
+		state = { kind: "loading" };
+		fetchBattle(gameId, turn, battleId)
+			.then((report) => {
+				state = { kind: "ready", report };
+			})
+			.catch((err: unknown) => {
+				if (err instanceof BattleFetchError && err.status === 404) {
+					state = { kind: "not_found" };
+				} else {
+					state = {
+						kind: "error",
+						message: err instanceof Error ? err.message : String(err),
+					};
+				}
+			});
+	});
+
+	function backToReport() {
+		goto(`/games/${gameId}/report`);
+	}
+	function backToMap() {
+		goto(`/games/${gameId}/map`);
+	}
 </script>
 
-<section class="active-view" data-testid="active-view-battle" data-battle-id={battleId}>
-	<h2>{i18n.t("game.view.battle")}</h2>
-	<p>{i18n.t("game.shell.coming_soon")}</p>
+<section
+	class="active-view"
+	data-testid="active-view-battle"
+	data-battle-id={battleId}
+>
+	{#if state.kind === "loading"}
+		<p class="status" data-testid="battle-loading">
+			{i18n.t("game.battle.loading")}
+		</p>
+	{:else if state.kind === "ready"}
+		<BattleViewer
+			report={state.report}
+			{shipClassLookup}
+			onBackToMap={backToMap}
+			onBackToReport={backToReport}
+		/>
+	{:else if state.kind === "not_found"}
+		<p class="status" data-testid="battle-not-found">
+			{i18n.t("game.battle.not_found")}
+		</p>
+	{:else}
+		<p class="status error" data-testid="battle-error">{state.message}</p>
+	{/if}
 </section>
 
 <style>
 	.active-view {
-		padding: 1.5rem;
+		display: flex;
+		flex-direction: column;
+		/*
+		 * The in-game shell renders this active view inside an
+		 * `.active-view-host` with `flex: 1; overflow-y: auto`, but
+		 * the surrounding `.game-shell` uses `min-height: 100vh`, so
+		 * without a hard upper bound the viewer pushes the whole
+		 * shell past the viewport. We pin the active view to `100dvh`
+		 * minus a small allowance for the header chrome (in-game
+		 * Header + optional HistoryBanner ≈ 66 px on desktop) so the
+		 * internal flex chain can split the remaining height between
+		 * the scene, scrubber, controls and log without forcing a
+		 * page-level scroll.
+		 */
+		height: calc(100dvh - 80px);
+		max-height: calc(100dvh - 80px);
+		min-height: 0;
+		overflow: hidden;
+		box-sizing: border-box;
 		font-family: system-ui, sans-serif;
+		color: #d6dcf2;
 	}
-	.active-view h2 {
-		margin: 0 0 0.5rem;
-		font-size: 1.1rem;
+	.status {
+		margin: 2rem auto;
+		max-width: 880px;
+		color: #93a0d0;
+		font-size: 0.95rem;
+		text-align: center;
 	}
-	.active-view p {
-		margin: 0;
-		color: #555;
+	.status.error {
+		color: #e08585;
 	}
 </style>

ui/frontend/src/lib/active-view/map.svelte

@@ -21,6 +21,8 @@ preference the store already manages.
 -->
 <script lang="ts">
 	import { getContext, onDestroy, onMount, untrack } from "svelte";
+	import { goto } from "$app/navigation";
+	import { page } from "$app/state";
 	import { i18n } from "$lib/i18n/index.svelte";
 	import {
 		createRenderer,
@@ -402,13 +404,40 @@ preference the store already manages.
 		if (selection === undefined) return;
 		const hit = handle.hitAt(cursorPx);
 		if (hit === null) return;
-		if (hit.primitive.kind !== "point") return;
 		const target = hitLookup.get(hit.primitive.id);
 		if (target === undefined) return;
-		if (target.kind === "planet") {
-			selection.selectPlanet(target.number);
-		} else {
-			selection.selectShipGroup(target.ref);
+		switch (target.kind) {
+			case "planet":
+				if (hit.primitive.kind !== "point") return;
+				selection.selectPlanet(target.number);
+				break;
+			case "shipGroup":
+				if (hit.primitive.kind !== "point") return;
+				selection.selectShipGroup(target.ref);
+				break;
+			case "battle": {
+				const gameId = page.params.id ?? "";
+				const turn = store?.report?.turn ?? 0;
+				void goto(
+					`/games/${gameId}/battle/${target.battleId}?turn=${turn}`,
+				);
+				break;
+			}
+			case "bombing": {
+				const gameId = page.params.id ?? "";
+				void goto(
+					`/games/${gameId}/report#report-bombings`,
+				).then(() => {
+					if (typeof document === "undefined") return;
+					const row = document.querySelector(
+						`[data-testid="report-bombing-row"][data-planet="${target.planet}"]`,
+					);
+					if (row && row.scrollIntoView) {
+						row.scrollIntoView({ behavior: "smooth", block: "center" });
+					}
+				});
+				break;
+			}
 		}
 	}
 

ui/frontend/src/lib/active-view/report/section-battles.svelte

@@ -1,13 +1,14 @@
 <!--
-Phase 23 Report View — battles section. The wire only carries
-battle UUIDs (the full battle report is fetched lazily by Phase 27),
-so each row is a monospace, non-interactive `<span>` of the battle
-identifier. Phase 27 will turn each row into a link to
-`/games/<id>/battle/<uuid>`; until then dead links are worse than
-plain text.
+Phase 27 Report View — battles section. Each row is a link into the
+Battle Viewer at `/games/<id>/battle/<uuid>?turn=<turn>` where
+`turn` follows the current report's turn so history-mode views land
+on the right battle. Phase 23 rendered the same rows as inactive
+monospace `<span>`; the rewire here is the one-liner the Phase 23
+decision log called out.
 -->
 <script lang="ts">
 	import { getContext } from "svelte";
+	import { page } from "$app/state";
 
 	import { i18n } from "$lib/i18n/index.svelte";
 	import {
@@ -19,7 +20,9 @@ plain text.
 		RENDERED_REPORT_CONTEXT_KEY,
 	);
 	const report = $derived(rendered?.report ?? null);
-	const ids = $derived(report?.battleIds ?? []);
+	const battles = $derived(report?.battles ?? []);
+	const gameId = $derived(page.params.id ?? "");
+	const turn = $derived(report?.turn ?? 0);
 </script>
 
 <section
@@ -31,22 +34,23 @@ plain text.
 
 	{#if report === null}
 		<p class="status">{i18n.t("game.report.loading")}</p>
-	{:else if ids.length === 0}
+	{:else if battles.length === 0}
 		<p class="status" data-testid="battles-empty">
 			{i18n.t("game.report.section.battles.empty")}
 		</p>
 	{:else}
 		<ul class="ids" data-testid="battles-list">
-			{#each ids as id (id)}
+			{#each battles as b (b.id)}
 				<li>
 					<span class="label">
 						{i18n.t("game.report.section.battles.id_label")}
 					</span>
-					<span
+					<a
 						class="uuid"
+						href={`/games/${gameId}/battle/${b.id}?turn=${turn}`}
 						data-testid="report-battle-row"
-						data-id={id}
-					>{id}</span>
+						data-id={b.id}
+					>{b.id}</a>
 				</li>
 			{/each}
 		</ul>
@@ -87,5 +91,10 @@ plain text.
 	.uuid {
 		color: #cfd7ff;
 		font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
+		text-decoration: underline;
+		text-underline-offset: 2px;
+	}
+	.uuid:hover {
+		color: #ffffff;
 	}
 </style>

ui/frontend/src/lib/battle-player/battle-scene.svelte

@@ -0,0 +1,438 @@
+<!--
+BattleScene — radial SVG visualisation of one battle frame.
+
+Layout: planet at the centre, race anchors equally spaced on an
+outer ring, each race rendered as a *cloud* of class circles
+arranged on a Vogel sunflower spiral. Spiral positions are
+reassigned per rank by their inward distance toward the planet so
+the rank-0 bucket (the bucket with the largest initial ship count)
+always sits at the most-inward Vogel slot.
+
+Tech-variant groups of the same `(race, className)` collapse to one
+visual node — per-tech detail lives in Reports. Each circle's
+radius scales with the per-ship FullMass (sqrt) so heavy ships
+visually dominate. Order, position, radius and mass are locked at
+battle start; only NumberLeft (the label number) and per-bucket
+visibility change per frame. Empty buckets are hidden so the
+remaining ones keep their original spots without reshuffling.
+
+Observer groups (`inBattle === false`) are filtered out by
+`buildFrames`. Same-race opponents are forbidden by the engine's
+combat filter, so a shot never collapses to a single visual node.
+-->
+<script lang="ts">
+	import { getContext } from "svelte";
+
+	import type { BattleReport } from "../../api/battle-fetch";
+	import {
+		CORE_CONTEXT_KEY,
+		type CoreHandle,
+	} from "$lib/core-context.svelte";
+	import { layoutRaces } from "./radial-layout";
+	import {
+		computeBattleGroupMass,
+		radiusForMass,
+		MAX_RADIUS,
+		type ShipClassLookup,
+	} from "./mass";
+	import {
+		buildGroupRaceMap,
+		normaliseGroups,
+		type Frame,
+	} from "./timeline";
+
+	let {
+		report,
+		frame,
+		shipClassLookup,
+		shotVisible = true,
+	}: {
+		report: BattleReport;
+		frame: Frame;
+		shipClassLookup?: ShipClassLookup;
+		shotVisible?: boolean;
+	} = $props();
+
+	const VIEW_BOX = 800;
+	const CENTER = { x: VIEW_BOX / 2, y: VIEW_BOX / 2 };
+	const PLANET_RADIUS = 60;
+	const RACE_RING_RADIUS = 280;
+	const BASE_STEP = 1.8 * MAX_RADIUS;
+	const GOLDEN_ANGLE = Math.PI * (3 - Math.sqrt(5));
+	const MAX_CLUSTER_RADIUS = 0.6 * (RACE_RING_RADIUS - PLANET_RADIUS);
+	const LABEL_MIN_Y = 24;
+
+	const coreHandle = getContext<CoreHandle | undefined>(CORE_CONTEXT_KEY);
+
+	const groupRace = $derived(buildGroupRaceMap(report.protocol));
+	const allGroups = $derived(normaliseGroups(report));
+
+	type StaticBucket = {
+		bucketKey: string;
+		className: string;
+		race: string;
+		raceId: number;
+		groupKeys: number[];
+		initialNum: number;
+		mass: number;
+		radius: number;
+		// Local offsets in the cluster's (u, v) basis. `u` always
+		// points from the race anchor toward the planet, so a
+		// constant local-frame layout produces the same "inward" feel
+		// regardless of which slot on the outer ring the race
+		// currently occupies (races rotate when peers die).
+		offsetU: number;
+		offsetV: number;
+	};
+
+	// staticBucketsByRace locks the bucket roster, ordering, masses,
+	// radii and local positions for the lifetime of this viewer. The
+	// derivation only re-runs when `report` or the wasm `core` flip
+	// (initial mount and core boot completion). Per-frame NumberLeft
+	// changes do not touch this map — they live in `renderedByRace`.
+	const staticBucketsByRace = $derived.by(() => {
+		const core = coreHandle?.core ?? null;
+		const out = new Map<number, StaticBucket[]>();
+		const bucketIndex = new Map<string, StaticBucket>();
+		for (const g of allGroups) {
+			const bucketKey = `${g.raceId}::${g.group.className}`;
+			let bucket = bucketIndex.get(bucketKey);
+			if (bucket === undefined) {
+				const classDef =
+					shipClassLookup?.get(g.group.race, g.group.className) ?? null;
+				const mass = core
+					? computeBattleGroupMass(g.group, classDef, core)
+					: 0;
+				bucket = {
+					bucketKey,
+					className: g.group.className,
+					race: g.group.race,
+					raceId: g.raceId,
+					groupKeys: [],
+					initialNum: 0,
+					mass,
+					radius: MAX_RADIUS,
+					offsetU: 0,
+					offsetV: 0,
+				};
+				bucketIndex.set(bucketKey, bucket);
+				const list = out.get(g.raceId) ?? [];
+				list.push(bucket);
+				out.set(g.raceId, list);
+			}
+			bucket.groupKeys.push(g.key);
+			bucket.initialNum += g.group.num;
+		}
+
+		// Per-battle mass normalisation: the heaviest bucket renders
+		// at MAX_RADIUS; lighter ones scale by sqrt(m/max).
+		let maxMass = 0;
+		for (const bucket of bucketIndex.values()) {
+			if (bucket.mass > maxMass) maxMass = bucket.mass;
+		}
+		for (const bucket of bucketIndex.values()) {
+			bucket.radius = radiusForMass(bucket.mass, maxMass);
+		}
+
+		// Sort each race's buckets by initial count (descending) +
+		// className as a stable tie-break, then assign Vogel positions
+		// reordered by inward dot product (offsetU desc) so the
+		// largest-by-num bucket lands at the most-inward Vogel slot.
+		for (const list of out.values()) {
+			list.sort((a, b) => {
+				if (b.initialNum !== a.initialNum) return b.initialNum - a.initialNum;
+				return a.className.localeCompare(b.className);
+			});
+			const N = list.length;
+			const denom = Math.max(1, Math.sqrt(Math.max(N, 1)));
+			const step = Math.min(BASE_STEP, MAX_CLUSTER_RADIUS / denom);
+			const positions = Array.from({ length: N }, (_, r) => {
+				const radius = step * Math.sqrt(r);
+				const angle = r * GOLDEN_ANGLE;
+				return {
+					offsetU: radius * Math.cos(angle),
+					offsetV: radius * Math.sin(angle),
+				};
+			});
+			positions.sort((a, b) => {
+				if (b.offsetU !== a.offsetU) return b.offsetU - a.offsetU;
+				return a.offsetV - b.offsetV;
+			});
+			for (let r = 0; r < N; r++) {
+				list[r].offsetU = positions[r].offsetU;
+				list[r].offsetV = positions[r].offsetV;
+			}
+		}
+		return out;
+	});
+
+	type RenderedBucket = StaticBucket & { numLeft: number };
+
+	// renderedByRace overlays the per-frame `remaining` map onto the
+	// static cluster: only buckets with `numLeft > 0` survive into
+	// the render list, so an emptied class disappears from the cloud
+	// while its neighbours keep their slots.
+	const renderedByRace = $derived.by(() => {
+		const out = new Map<number, RenderedBucket[]>();
+		for (const [raceId, list] of staticBucketsByRace) {
+			const filtered: RenderedBucket[] = [];
+			for (const bucket of list) {
+				let numLeft = 0;
+				for (const key of bucket.groupKeys) {
+					numLeft += frame.remaining.get(key) ?? 0;
+				}
+				if (numLeft > 0) filtered.push({ ...bucket, numLeft });
+			}
+			if (filtered.length > 0) out.set(raceId, filtered);
+		}
+		return out;
+	});
+
+	// visibleBucketByGroupKey lets shot endpoints resolve to a node
+	// only when the bucket is currently rendered. A phantom shot
+	// against an already-empty bucket therefore returns `null` and
+	// no line is drawn.
+	const visibleBucketByGroupKey = $derived.by(() => {
+		const out = new Map<number, RenderedBucket>();
+		for (const list of renderedByRace.values()) {
+			for (const bucket of list) {
+				for (const key of bucket.groupKeys) {
+					out.set(key, bucket);
+				}
+			}
+		}
+		return out;
+	});
+
+	const raceLayout = $derived(
+		layoutRaces(frame.activeRaceIds, {
+			center: CENTER,
+			radius: RACE_RING_RADIUS,
+		}),
+	);
+
+	type ClusterBasis = {
+		anchorX: number;
+		anchorY: number;
+		ux: number;
+		uy: number;
+		vx: number;
+		vy: number;
+	};
+
+	const clusterBasisById = $derived.by(() => {
+		const out = new Map<number, ClusterBasis>();
+		for (const anchor of raceLayout) {
+			const dx = CENTER.x - anchor.x;
+			const dy = CENTER.y - anchor.y;
+			const len = Math.hypot(dx, dy) || 1;
+			const ux = dx / len;
+			const uy = dy / len;
+			const vx = uy;
+			const vy = -ux;
+			out.set(anchor.raceId, {
+				anchorX: anchor.x,
+				anchorY: anchor.y,
+				ux,
+				uy,
+				vx,
+				vy,
+			});
+		}
+		return out;
+	});
+
+	function worldPosition(basis: ClusterBasis, bucket: StaticBucket) {
+		return {
+			x: basis.anchorX + bucket.offsetU * basis.ux + bucket.offsetV * basis.vx,
+			y: basis.anchorY + bucket.offsetU * basis.uy + bucket.offsetV * basis.vy,
+		};
+	}
+
+	function findClassCircleCenter(groupKey: number) {
+		const bucket = visibleBucketByGroupKey.get(groupKey);
+		if (!bucket) return null;
+		const basis = clusterBasisById.get(bucket.raceId);
+		if (!basis) return null;
+		return worldPosition(basis, bucket);
+	}
+
+	const shotLine = $derived.by(() => {
+		const action = frame.lastAction;
+		if (!action) return null;
+		const from = findClassCircleCenter(action.sa);
+		const to = findClassCircleCenter(action.sd);
+		if (!from || !to) return null;
+		return { from, to, destroyed: action.x, defenderKey: action.sd };
+	});
+
+	const flashDefenderBucketKey = $derived.by(() => {
+		if (!shotLine || !shotVisible) return null;
+		const bucket = visibleBucketByGroupKey.get(shotLine.defenderKey);
+		return bucket?.bucketKey ?? null;
+	});
+
+	const raceLabelById = $derived.by(() => {
+		const out = new Map<number, string>();
+		for (const g of allGroups) {
+			out.set(g.raceId, g.group.race);
+		}
+		for (const [, raceId] of groupRace) {
+			if (!out.has(raceId)) out.set(raceId, `race ${raceId}`);
+		}
+		return out;
+	});
+
+	// raceLabelYById finds a y just above the visible cluster's top
+	// edge and clamps it to the SVG viewport so the north race
+	// (anchor near the top) never has its label clipped off-canvas.
+	const raceLabelYById = $derived.by(() => {
+		const out = new Map<number, number>();
+		for (const [raceId, list] of renderedByRace) {
+			const basis = clusterBasisById.get(raceId);
+			if (!basis || list.length === 0) continue;
+			let topY = basis.anchorY;
+			for (const bucket of list) {
+				const world = worldPosition(basis, bucket);
+				const top = world.y - bucket.radius;
+				if (top < topY) topY = top;
+			}
+			const fallback = basis.anchorY - MAX_RADIUS - 12;
+			const target = Math.min(topY - 12, fallback);
+			out.set(raceId, Math.max(target, LABEL_MIN_Y));
+		}
+		return out;
+	});
+</script>
+
+<svg
+	class="battle-scene"
+	viewBox="0 0 {VIEW_BOX} {VIEW_BOX}"
+	preserveAspectRatio="xMidYMid meet"
+	role="img"
+	aria-label="battle scene"
+	data-testid="battle-scene"
+>
+	<circle
+		cx={CENTER.x}
+		cy={CENTER.y}
+		r={PLANET_RADIUS}
+		class="planet"
+		data-testid="battle-scene-planet"
+	/>
+	<text
+		x={CENTER.x}
+		y={CENTER.y + PLANET_RADIUS + 24}
+		text-anchor="middle"
+		class="planet-label"
+	>{report.planetName} (#{report.planet})</text>
+
+	{#each raceLayout as anchor (anchor.raceId)}
+		{@const cluster = renderedByRace.get(anchor.raceId) ?? []}
+		{@const basis = clusterBasisById.get(anchor.raceId)}
+		{#if basis && cluster.length > 0}
+			<g
+				class="race-cluster"
+				data-testid="battle-race-cluster"
+				data-race-id={anchor.raceId}
+			>
+				<text
+					x={anchor.x}
+					y={raceLabelYById.get(anchor.raceId) ?? anchor.y - MAX_RADIUS - 12}
+					text-anchor="middle"
+					class="race-label"
+				>{raceLabelById.get(anchor.raceId) ?? `race ${anchor.raceId}`}</text>
+				{#each cluster as entry (entry.bucketKey)}
+					{@const pos = worldPosition(basis, entry)}
+					{@const flash =
+						entry.bucketKey === flashDefenderBucketKey
+							? shotLine?.destroyed
+								? "destroyed"
+								: "shielded"
+							: null}
+					<g
+						class="class-marker"
+						data-testid="battle-class-marker"
+						data-bucket-key={entry.bucketKey}
+						data-class-name={entry.className}
+						data-flash={flash}
+					>
+						<circle cx={pos.x} cy={pos.y} r={entry.radius} />
+						<text
+							x={pos.x}
+							y={pos.y + entry.radius + 12}
+							text-anchor="middle"
+							class="class-label"
+						>{entry.className}:{entry.numLeft}</text>
+					</g>
+				{/each}
+			</g>
+		{/if}
+	{/each}
+
+	{#if shotLine && shotVisible}
+		<line
+			x1={shotLine.from.x}
+			y1={shotLine.from.y}
+			x2={shotLine.to.x}
+			y2={shotLine.to.y}
+			class="shot"
+			class:destroyed={shotLine.destroyed}
+			data-testid="battle-shot"
+			data-destroyed={shotLine.destroyed ? "true" : "false"}
+		/>
+	{/if}
+</svg>
+
+<style>
+	.battle-scene {
+		width: 100%;
+		height: 100%;
+		background: #0a0d1a;
+		display: block;
+	}
+	.planet {
+		fill: #2a2f40;
+		stroke: #4a5066;
+		stroke-width: 1.5;
+	}
+	.planet-label {
+		fill: #6d7388;
+		font-size: 18px;
+		font-family: ui-sans-serif, system-ui, sans-serif;
+	}
+	.race-label {
+		fill: #e2e6ff;
+		font-size: 16px;
+		font-weight: 600;
+		font-family: ui-sans-serif, system-ui, sans-serif;
+	}
+	.class-marker circle {
+		fill: #1a2042;
+		stroke: #6d7bb5;
+		stroke-width: 1.5;
+		transition:
+			fill 80ms ease-in,
+			stroke 80ms ease-in;
+	}
+	.class-marker[data-flash="destroyed"] circle {
+		fill: #ee3344;
+		stroke: #ee3344;
+	}
+	.class-marker[data-flash="shielded"] circle {
+		fill: #44dd66;
+		stroke: #44dd66;
+	}
+	.class-label {
+		fill: #b8c0e6;
+		font-size: 11px;
+		font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
+	}
+	.shot {
+		stroke: #44dd66;
+		stroke-width: 2;
+	}
+	.shot.destroyed {
+		stroke: #ee3344;
+	}
+</style>

ui/frontend/src/lib/battle-player/battle-viewer.svelte

@@ -0,0 +1,348 @@
+<!--
+BattleViewer — orchestrates the radial battle scene, the playback
+controls, and the accessibility text log for one BattleReport. Owns
+the playback state (`frameIndex`, `playing`, `speed`, `logOpen`).
+Layout reorganisation (latest iteration):
+
+- The header carries the planet title, the back-navigation links and
+  the frame counter so the scene captures the full viewer width and
+  height beneath them.
+- A drag-seek slider sits between the scene and the controls; the
+  user can scrub the playback timeline at any speed.
+- The text log collapses behind a toggle in the controls bar so a
+  user who wants the biggest scene possible can hide it entirely.
+
+The component is logically isolated: feed it any `BattleReport`
+matching `pkg/model/report/battle.go` and it plays back.
+-->
+<script lang="ts">
+	import { i18n } from "$lib/i18n/index.svelte";
+	import type { BattleReport } from "../../api/battle-fetch";
+	import type { ShipClassLookup } from "./mass";
+
+	import BattleScene from "./battle-scene.svelte";
+	import PlaybackControls, {
+		type PlaybackSpeed,
+	} from "./playback-controls.svelte";
+	import { buildFrames } from "./timeline";
+
+	let {
+		report,
+		shipClassLookup,
+		onBackToMap,
+		onBackToReport,
+	}: {
+		report: BattleReport;
+		shipClassLookup?: ShipClassLookup;
+		onBackToMap?: () => void;
+		onBackToReport?: () => void;
+	} = $props();
+
+	const frames = $derived(buildFrames(report));
+	let frameIndex = $state(0);
+	let playing = $state(false);
+	let speed = $state<PlaybackSpeed>(1);
+	let logOpen = $state(true);
+	let shotVisible = $state(true);
+	let logEl = $state<HTMLOListElement | null>(null);
+
+	const rawFrame = $derived(frames[Math.min(frameIndex, frames.length - 1)]);
+
+	// displayFrame freezes the layout at the penultimate frame's
+	// state once the protocol's last action eliminates a race, so
+	// the surviving cluster does not suddenly reflow onto the
+	// planet ring on the very last shot. The frame counter still
+	// advances to the final shot and `lastAction` still drives the
+	// killing line + flash; only `remaining` and `activeRaceIds`
+	// (the layout-determining state) freeze.
+	const displayFrame = $derived.by(() => {
+		const last = frames.length - 1;
+		if (
+			frameIndex === last &&
+			last >= 1 &&
+			frames[last].activeRaceIds.length < frames[last - 1].activeRaceIds.length
+		) {
+			const prev = frames[last - 1];
+			const cur = frames[last];
+			return {
+				shotIndex: cur.shotIndex,
+				lastAction: cur.lastAction,
+				remaining: prev.remaining,
+				activeRaceIds: prev.activeRaceIds,
+			};
+		}
+		return rawFrame;
+	});
+
+	// One tick per frame: blink the shot line off during the last
+	// 10 % of the frame's interval, then advance. Effect re-arms
+	// whenever frameIndex / playing / speed changes; previous
+	// timers clean up through the return.
+	$effect(() => {
+		void frameIndex;
+		void speed;
+		shotVisible = true;
+		if (!playing) return;
+		const intervalMs = 400 / speed;
+		const blinkOff = setTimeout(() => {
+			shotVisible = false;
+		}, intervalMs * 0.9);
+		const advance = setTimeout(() => {
+			if (frameIndex >= frames.length - 1) {
+				playing = false;
+				return;
+			}
+			frameIndex = frameIndex + 1;
+		}, intervalMs);
+		return () => {
+			clearTimeout(blinkOff);
+			clearTimeout(advance);
+		};
+	});
+
+	// Auto-scroll the visible log row into view so the highlight
+	// keeps up with the timeline on long battles.
+	$effect(() => {
+		void displayFrame.shotIndex;
+		if (!logOpen || logEl === null) return;
+		const current = logEl.querySelector(
+			'li[data-current="true"]',
+		) as HTMLElement | null;
+		if (current !== null) {
+			current.scrollIntoView({ block: "nearest", behavior: "smooth" });
+		}
+	});
+
+	function seekToShot(actionIndex: number) {
+		playing = false;
+		frameIndex = Math.max(
+			0,
+			Math.min(frames.length - 1, actionIndex + 1),
+		);
+	}
+
+	function onScrub(event: Event) {
+		const target = event.currentTarget as HTMLInputElement;
+		const value = Number(target.value);
+		if (!Number.isFinite(value)) return;
+		playing = false;
+		frameIndex = Math.max(0, Math.min(frames.length - 1, Math.trunc(value)));
+	}
+
+	function describeAction(index: number): string {
+		const action = report.protocol[index];
+		const attackerGroup = report.ships[String(action.sa)];
+		const defenderGroup = report.ships[String(action.sd)];
+		const attackerRace = attackerGroup?.race ?? `race ${action.a}`;
+		const attackerClass = attackerGroup?.className ?? `class ${action.sa}`;
+		const defenderRace = defenderGroup?.race ?? `race ${action.d}`;
+		const defenderClass = defenderGroup?.className ?? `class ${action.sd}`;
+		const key = action.x
+			? "game.battle.log.destroyed"
+			: "game.battle.log.shielded";
+		return i18n.t(key, {
+			attacker_race: attackerRace,
+			attacker_class: attackerClass,
+			defender_race: defenderRace,
+			defender_class: defenderClass,
+		});
+	}
+</script>
+
+<div class="viewer" data-testid="battle-viewer">
+	<header class="header">
+		<div class="back-row">
+			{#if onBackToMap}
+				<button
+					type="button"
+					class="back-btn"
+					onclick={onBackToMap}
+					data-testid="battle-back-to-map"
+				>{i18n.t("game.battle.back_to_map")}</button>
+			{/if}
+			{#if onBackToReport}
+				<button
+					type="button"
+					class="back-btn"
+					onclick={onBackToReport}
+					data-testid="battle-back-to-report"
+				>{i18n.t("game.battle.back_to_report")}</button>
+			{/if}
+		</div>
+		<h2 data-testid="battle-viewer-title">
+			{i18n.t("game.battle.header_title", {
+				planet_name: report.planetName,
+				planet_number: String(report.planet),
+			})}
+		</h2>
+		<span class="progress" data-testid="battle-frame-index">
+			{displayFrame.shotIndex} / {report.protocol.length}
+		</span>
+	</header>
+
+	<div class="scene">
+		<BattleScene {report} frame={displayFrame} {shipClassLookup} {shotVisible} />
+	</div>
+
+	<input
+		class="scrubber"
+		type="range"
+		min="0"
+		max={Math.max(0, frames.length - 1)}
+		step="1"
+		value={frameIndex}
+		oninput={onScrub}
+		aria-label={i18n.t("game.battle.controls.scrub")}
+		data-testid="battle-scrubber"
+	/>
+
+	<PlaybackControls
+		bind:playing
+		bind:frameIndex
+		bind:speed
+		bind:logOpen
+		frameCount={frames.length}
+	/>
+
+	{#if logOpen}
+		<section
+			class="log"
+			aria-label={i18n.t("game.battle.accessibility.protocol_heading")}
+		>
+			<h3>{i18n.t("game.battle.accessibility.protocol_heading")}</h3>
+			<ol bind:this={logEl} data-testid="battle-protocol-log">
+				{#each report.protocol as _action, i (i)}
+					<li
+						data-testid="battle-protocol-log-item"
+						data-current={i + 1 === displayFrame.shotIndex ? "true" : "false"}
+					>
+						<button
+							type="button"
+							class="log-row-btn"
+							onclick={() => seekToShot(i)}
+						>{describeAction(i)}</button>
+					</li>
+				{/each}
+			</ol>
+		</section>
+	{/if}
+</div>
+
+<style>
+	.viewer {
+		display: flex;
+		flex-direction: column;
+		gap: 0.5rem;
+		width: 100%;
+		flex: 1 1 auto;
+		min-height: 0;
+		margin: 0 auto;
+		padding: 0.75rem 1rem;
+		color: #d6dcf2;
+		font-family: inherit;
+		box-sizing: border-box;
+	}
+	.header {
+		display: flex;
+		align-items: center;
+		gap: 0.75rem;
+		flex: 0 0 auto;
+	}
+	.header h2 {
+		flex: 1 1 auto;
+		margin: 0;
+		font-size: 1.05rem;
+		text-transform: uppercase;
+		letter-spacing: 0.04em;
+		text-align: center;
+	}
+	.back-row {
+		display: flex;
+		gap: 0.3rem;
+		flex: 0 0 auto;
+	}
+	.back-btn {
+		appearance: none;
+		background: #1f2748;
+		color: #d6dcf2;
+		border: 1px solid #2c3568;
+		padding: 0.3rem 0.6rem;
+		border-radius: 3px;
+		cursor: pointer;
+		font-size: 0.8rem;
+	}
+	.back-btn:hover {
+		background: #2a3463;
+	}
+	.progress {
+		color: #93a0d0;
+		font-variant-numeric: tabular-nums;
+		font-size: 0.85rem;
+		flex: 0 0 auto;
+		min-width: 5rem;
+		text-align: right;
+	}
+	.scene {
+		background: #0a0d1a;
+		border: 1px solid #1e264a;
+		border-radius: 4px;
+		overflow: hidden;
+		flex: 1 1 auto;
+		min-height: 0;
+	}
+	.scrubber {
+		width: 100%;
+		margin: 0;
+		flex: 0 0 auto;
+		accent-color: #6d7bb5;
+	}
+	.log {
+		flex: 0 1 auto;
+		min-height: 4rem;
+		max-height: 30vh;
+		overflow-y: auto;
+		display: flex;
+		flex-direction: column;
+	}
+	.log h3 {
+		margin: 0 0 0.3rem;
+		color: #93a0d0;
+		font-size: 0.75rem;
+		text-transform: uppercase;
+		letter-spacing: 0.05em;
+		flex: 0 0 auto;
+	}
+	.log ol {
+		list-style: none;
+		margin: 0;
+		padding: 0;
+		font-size: 0.85rem;
+		overflow-y: auto;
+		color: #c6cdf0;
+		flex: 1 1 auto;
+		min-height: 0;
+	}
+	.log li {
+		border-bottom: 1px solid #1c2240;
+	}
+	.log-row-btn {
+		display: block;
+		width: 100%;
+		text-align: left;
+		padding: 0.15rem 0.4rem;
+		background: transparent;
+		border: 0;
+		color: inherit;
+		font: inherit;
+		cursor: pointer;
+	}
+	.log-row-btn:hover,
+	.log-row-btn:focus-visible {
+		background: #131a36;
+	}
+	.log li[data-current="true"] .log-row-btn {
+		color: #ffe27a;
+		font-weight: 600;
+		background: #1a2240;
+	}
+</style>

ui/frontend/src/lib/battle-player/mass.ts

@@ -0,0 +1,109 @@
+// Mass helpers for the Battle Viewer.
+//
+// Phase 27 refinement: ship-class circles are sized by per-ship
+// FullMass (Empty + carrying), with a 6..24 px range. The viewer
+// resolves a `(race, className) → ShipClassRef` lookup from the
+// surrounding GameReport's `localShipClass` / `otherShipClass`
+// tables and feeds it through the wasm bridge to `pkg/calc/ship.go`.
+//
+// Pure utilities live here; the Svelte components consume them.
+
+import type { Core } from "../../platform/core/index";
+import type { BattleReportGroup } from "../../api/battle-fetch";
+
+/** Smallest visible ship circle. Picked so the `<class>:<n>` label
+ * stays legible on every viewport. */
+export const MIN_RADIUS = 6;
+
+/** Largest ship circle. Matches the Phase-27 baseline so heavy
+ * ships keep their previous visual prominence. */
+export const MAX_RADIUS = 24;
+
+/**
+ * ShipClassRef is the minimum slice of a ship class needed to
+ * compute its mass. Mirrors the relevant fields of
+ * `ShipClassSummary` (own classes) and `ReportOtherShipClass`
+ * (foreign classes) without coupling the viewer to either type.
+ */
+export interface ShipClassRef {
+	drive: number;
+	weapons: number;
+	armament: number;
+	shields: number;
+	cargo: number;
+}
+
+/**
+ * ShipClassLookup resolves `(race, className)` to a ship-class
+ * descriptor. Returns `null` when the class is not in the parent
+ * report — happens with legacy-mode foreign races that lack a
+ * `<Race> Ship Types` block.
+ */
+export interface ShipClassLookup {
+	get(race: string, className: string): ShipClassRef | null;
+}
+
+/**
+ * computeBattleGroupMass returns the per-ship FullMass for a given
+ * battle group. Mass=0 means "unknown" — either the wasm bridge
+ * rejected the ship-class params (degenerate weapons/armament pair)
+ * or the class did not resolve in the lookup. Either way the
+ * caller's downstream `radiusForMass` falls back to MAX_RADIUS so
+ * the node stays visible.
+ *
+ * Cargo never changes during a battle, so this can be cached per
+ * `(race, className)` bucket for the lifetime of the viewer
+ * session.
+ */
+export function computeBattleGroupMass(
+	group: BattleReportGroup,
+	classDef: ShipClassRef | null,
+	core: Core,
+): number {
+	if (classDef === null) return 0;
+	const empty = core.emptyMass({
+		drive: classDef.drive,
+		weapons: classDef.weapons,
+		armament: classDef.armament,
+		shields: classDef.shields,
+		cargo: classDef.cargo,
+	});
+	if (empty === null) return 0;
+	const cargoTech = classDef.cargo * (group.tech.CARGO ?? 0);
+	const carrying = core.carryingMass({
+		load: group.loadQuantity,
+		cargoTech,
+	});
+	return core.fullMass({ emptyMass: empty, carryingMass: carrying });
+}
+
+/**
+ * radiusForMass maps an absolute ship mass to a circle radius via
+ * a per-battle normalisation: the heaviest visual node always
+ * renders at MAX_RADIUS, lighter ones scale by sqrt(mass /
+ * maxMassInBattle) so the smallest ships don't disappear and the
+ * heaviest ones don't dominate the scene at >MAX_RADIUS. mass<=0
+ * falls back to MAX_RADIUS so unresolved/invalid classes stay
+ * visible.
+ */
+export function radiusForMass(mass: number, maxMassInBattle: number): number {
+	if (maxMassInBattle <= 0 || mass <= 0) return MAX_RADIUS;
+	const scaled = MIN_RADIUS + (MAX_RADIUS - MIN_RADIUS) * Math.sqrt(mass / maxMassInBattle);
+	if (scaled < MIN_RADIUS) return MIN_RADIUS;
+	if (scaled > MAX_RADIUS) return MAX_RADIUS;
+	return scaled;
+}
+
+/**
+ * MapShipClassLookup is a `Map<string, ShipClassRef>`-backed
+ * implementation of `ShipClassLookup`. Key encoding mirrors the
+ * one battle.svelte uses when populating the lookup from the
+ * parent GameReport.
+ */
+export class MapShipClassLookup implements ShipClassLookup {
+	constructor(private readonly map: Map<string, ShipClassRef>) {}
+
+	get(race: string, className: string): ShipClassRef | null {
+		return this.map.get(`${race}::${className}`) ?? null;
+	}
+}

ui/frontend/src/lib/battle-player/playback-controls.svelte

@@ -0,0 +1,155 @@
+<!--
+PlaybackControls — rewind / step-back / play-pause / step-forward
+plus a single cycling speed button (1x → 2x → 4x → 6x → 1x) and a
+"log" toggle that the orchestrator uses to collapse the always-on
+text protocol when the user wants more space for the scene. Owns no
+state of its own; binds `playing`, `frameIndex`, `speed`, and
+`logOpen` from the orchestrator. Disables step/rewind when there's
+nowhere to go and step-forward when the timeline is at its end.
+-->
+<script lang="ts">
+	import { i18n } from "$lib/i18n/index.svelte";
+
+	export type PlaybackSpeed = 1 | 2 | 4 | 6;
+
+	const SPEED_CYCLE: PlaybackSpeed[] = [1, 2, 4, 6];
+
+	let {
+		playing = $bindable(),
+		frameIndex = $bindable(),
+		speed = $bindable(),
+		logOpen = $bindable(),
+		frameCount,
+	}: {
+		playing: boolean;
+		frameIndex: number;
+		speed: PlaybackSpeed;
+		logOpen: boolean;
+		frameCount: number;
+	} = $props();
+
+	function rewind() {
+		playing = false;
+		frameIndex = 0;
+	}
+	function stepBack() {
+		playing = false;
+		if (frameIndex > 0) frameIndex = frameIndex - 1;
+	}
+	function togglePlay() {
+		if (frameIndex >= frameCount - 1) {
+			frameIndex = 0;
+		}
+		playing = !playing;
+	}
+	function stepForward() {
+		playing = false;
+		if (frameIndex < frameCount - 1) frameIndex = frameIndex + 1;
+	}
+	function cycleSpeed() {
+		const idx = SPEED_CYCLE.indexOf(speed);
+		const next = SPEED_CYCLE[(idx + 1) % SPEED_CYCLE.length];
+		speed = next;
+	}
+	function toggleLog() {
+		logOpen = !logOpen;
+	}
+
+	const speedLabel = $derived(`${speed}x`);
+</script>
+
+<div class="controls" data-testid="battle-controls">
+	<button
+		type="button"
+		onclick={rewind}
+		disabled={frameIndex === 0}
+		aria-label={i18n.t("game.battle.controls.rewind")}
+		data-testid="battle-control-rewind"
+	>⏮</button>
+	<button
+		type="button"
+		onclick={stepBack}
+		disabled={frameIndex === 0}
+		aria-label={i18n.t("game.battle.controls.step_backward")}
+		data-testid="battle-control-step-back"
+	>◀︎◀︎</button>
+	<button
+		type="button"
+		onclick={togglePlay}
+		aria-label={playing
+			? i18n.t("game.battle.controls.pause")
+			: i18n.t("game.battle.controls.play")}
+		data-testid="battle-control-play"
+		data-playing={playing ? "true" : "false"}
+	>{playing ? "⏸" : "▶︎"}</button>
+	<button
+		type="button"
+		onclick={stepForward}
+		disabled={frameIndex >= frameCount - 1}
+		aria-label={i18n.t("game.battle.controls.step_forward")}
+		data-testid="battle-control-step-forward"
+	>▶︎▶︎</button>
+
+	<div class="spacer" aria-hidden="true"></div>
+
+	<button
+		type="button"
+		class="speed-btn"
+		onclick={cycleSpeed}
+		title={i18n.t("game.battle.controls.speed_label")}
+		aria-label={i18n.t("game.battle.controls.speed_label")}
+		data-testid="battle-control-speed"
+		data-speed={speed}
+	>{speedLabel}</button>
+
+	<button
+		type="button"
+		class="log-toggle"
+		class:active={logOpen}
+		onclick={toggleLog}
+		aria-pressed={logOpen}
+		aria-label={i18n.t("game.battle.controls.log_toggle")}
+		data-testid="battle-control-log-toggle"
+	>{i18n.t("game.battle.controls.log_toggle")} {logOpen ? "▲" : "▼"}</button>
+</div>
+
+<style>
+	.controls {
+		display: flex;
+		align-items: center;
+		gap: 0.4rem;
+		padding: 0.5rem 0.75rem;
+		background: #131934;
+		border: 1px solid #1e264a;
+		border-radius: 4px;
+	}
+	.spacer {
+		flex: 1 1 auto;
+	}
+	button {
+		appearance: none;
+		background: #1f2748;
+		color: #d6dcf2;
+		border: 1px solid #2c3568;
+		padding: 0.35rem 0.7rem;
+		border-radius: 3px;
+		cursor: pointer;
+		font-size: 0.9rem;
+		font-family: inherit;
+		min-width: 2.5rem;
+	}
+	button:hover:not(:disabled) {
+		background: #2a3463;
+	}
+	button:disabled {
+		opacity: 0.4;
+		cursor: not-allowed;
+	}
+	.speed-btn {
+		min-width: 3rem;
+		font-variant-numeric: tabular-nums;
+	}
+	.log-toggle.active {
+		background: #2a3463;
+	}
+</style>

ui/frontend/src/lib/battle-player/radial-layout.ts

@@ -0,0 +1,59 @@
+// Radial layout for the BattleViewer.
+//
+// Places race anchors on a circle of radius `radius` around `center`
+// at equal angular spacing. For three or more races the first anchor
+// sits at the top (12 o'clock) and subsequent anchors march
+// clockwise. For exactly two races the pair is rotated 90° so they
+// face each other horizontally (3 o'clock vs 9 o'clock) — that keeps
+// every race label clear of the SVG top edge when only two clusters
+// remain, and reads as "the two sides facing off" naturally.
+//
+// When a race is eliminated mid-battle the caller filters it out of
+// `activeRaceIds` and the survivors are re-spaced on the next frame
+// through the same helper.
+
+export interface RaceAnchor {
+	raceId: number;
+	x: number;
+	y: number;
+	/** Angle in radians measured from the positive Y axis clockwise. */
+	angle: number;
+}
+
+export interface RadialLayoutOptions {
+	center: { x: number; y: number };
+	radius: number;
+}
+
+/**
+ * layoutRaces returns anchor positions for each `activeRaceIds`
+ * entry, placed at equal angular spacing on a circle. The input
+ * order is preserved so consumers get a stable mapping across
+ * frames; eliminated entries should simply be filtered out before
+ * the call.
+ */
+export function layoutRaces(
+	activeRaceIds: number[],
+	options: RadialLayoutOptions,
+): RaceAnchor[] {
+	const count = activeRaceIds.length;
+	if (count === 0) return [];
+	const { center, radius } = options;
+	const out: RaceAnchor[] = [];
+	// For two participants we want a horizontal duel layout: race 0
+	// at 9 o'clock, race 1 at 3 o'clock. For any other count the
+	// first anchor lands at the top (12 o'clock) and the rest march
+	// clockwise at equal spacing.
+	const startAngle = count === 2 ? Math.PI : -Math.PI / 2;
+	for (let i = 0; i < count; i++) {
+		const step = (2 * Math.PI) / count;
+		const angle = startAngle + i * step;
+		out.push({
+			raceId: activeRaceIds[i],
+			x: center.x + radius * Math.cos(angle),
+			y: center.y + radius * Math.sin(angle),
+			angle,
+		});
+	}
+	return out;
+}

ui/frontend/src/lib/battle-player/timeline.ts

@@ -0,0 +1,143 @@
+// Timeline builder for the BattleViewer.
+//
+// Given a `BattleReport`, expands the flat `protocol` into a
+// sequence of frames. Frame 0 carries the initial state; frame N
+// (1 ≤ N ≤ protocol.length) reflects the state right after the
+// (N-1)-th action has been applied. Each frame is self-contained so
+// stepping forward and backward is a constant-time index lookup, no
+// rewind logic needed.
+
+import type {
+	BattleActionReport,
+	BattleReport,
+	BattleReportGroup,
+} from "../../api/battle-fetch";
+
+/**
+ * Frame is one tick of the battle playback. `remaining` carries the
+ * surviving ship count for each ship-group key from
+ * `BattleReport.ships`; `activeRaceIds` are the race indices with at
+ * least one surviving in-battle group. `lastAction` is the action
+ * applied to produce this frame, or `null` for the initial frame.
+ */
+export interface Frame {
+	shotIndex: number;
+	remaining: Map<number, number>;
+	activeRaceIds: number[];
+	lastAction: BattleActionReport | null;
+}
+
+export interface NormalisedGroup {
+	key: number;
+	group: BattleReportGroup;
+	raceId: number;
+}
+
+/**
+ * normaliseGroups returns the in-battle ship groups from a
+ * BattleReport indexed by their integer key. Observer groups
+ * (`inBattle === false`) are skipped because they are neither
+ * targeted nor drawn. The race index per group is derived from the
+ * protocol — every in-battle group appears at least once as
+ * attacker or defender, and the engine's pairing (a, sa) / (d, sd)
+ * defines the relationship.
+ */
+export function normaliseGroups(report: BattleReport): NormalisedGroup[] {
+	const raceByKey = buildGroupRaceMap(report.protocol);
+	const out: NormalisedGroup[] = [];
+	for (const [keyRaw, group] of Object.entries(report.ships)) {
+		if (!group.inBattle) continue;
+		const key = Number(keyRaw);
+		if (!Number.isFinite(key)) continue;
+		const raceId = raceByKey.get(key);
+		if (raceId === undefined) continue;
+		out.push({ key, group, raceId });
+	}
+	return out;
+}
+
+/**
+ * buildGroupRaceMap extracts the `ship-group key → race index`
+ * mapping from a battle protocol. Same key appearing twice always
+ * carries the same race index — protocol entries are emitted by the
+ * engine, which never crosses these wires.
+ */
+export function buildGroupRaceMap(
+	protocol: BattleActionReport[],
+): Map<number, number> {
+	const out = new Map<number, number>();
+	for (const action of protocol) {
+		if (!out.has(action.sa)) out.set(action.sa, action.a);
+		if (!out.has(action.sd)) out.set(action.sd, action.d);
+	}
+	return out;
+}
+
+/**
+ * buildFrames walks the protocol once and emits a frame after each
+ * applied action plus the initial frame. The remaining-ships map is
+ * cloned per frame so callers can step backward without manual
+ * bookkeeping. Eliminated races drop out of `activeRaceIds` as soon
+ * as their last in-battle group hits zero.
+ */
+export function buildFrames(report: BattleReport): Frame[] {
+	const groups = normaliseGroups(report);
+	const initialRemaining = new Map<number, number>();
+	const raceTotals = new Map<number, number>();
+	for (const g of groups) {
+		initialRemaining.set(g.key, g.group.num);
+		raceTotals.set(g.raceId, (raceTotals.get(g.raceId) ?? 0) + g.group.num);
+	}
+
+	const frames: Frame[] = [];
+	frames.push({
+		shotIndex: 0,
+		remaining: new Map(initialRemaining),
+		activeRaceIds: collectActiveRaces(raceTotals),
+		lastAction: null,
+	});
+
+	const groupRaceByKey = new Map<number, number>();
+	for (const g of groups) groupRaceByKey.set(g.key, g.raceId);
+
+	const current = new Map(initialRemaining);
+	const runningRaceTotals = new Map(raceTotals);
+	for (let i = 0; i < report.protocol.length; i++) {
+		const action = report.protocol[i];
+		if (action.x) {
+			// Defence in depth: a malformed protocol that fires more
+			// `Destroyed` rows than the group has ships would push
+			// `runningRaceTotals` below zero and drop the race from
+			// `activeRaceIds` prematurely. Real legacy data folds
+			// duplicate `(race, className)` roster rows into the
+			// same `BattleReportGroup` (parser + engine), so this
+			// branch is hit only on a real shrink — but the clamp
+			// keeps the math from going negative either way.
+			const left = current.get(action.sd) ?? 0;
+			if (left > 0) {
+				current.set(action.sd, left - 1);
+				const raceId = groupRaceByKey.get(action.sd);
+				if (raceId !== undefined) {
+					const t = (runningRaceTotals.get(raceId) ?? 0) - 1;
+					runningRaceTotals.set(raceId, Math.max(0, t));
+				}
+			}
+		}
+		frames.push({
+			shotIndex: i + 1,
+			remaining: new Map(current),
+			activeRaceIds: collectActiveRaces(runningRaceTotals),
+			lastAction: action,
+		});
+	}
+
+	return frames;
+}
+
+function collectActiveRaces(totals: Map<number, number>): number[] {
+	const out: number[] = [];
+	for (const [raceId, total] of totals.entries()) {
+		if (total > 0) out.push(raceId);
+	}
+	return out.sort((a, b) => a - b);
+}

ui/frontend/src/lib/game-state.svelte.ts

@@ -24,6 +24,12 @@ import type { WrapMode } from "../map/world";
 
 const PREF_NAMESPACE = "game-prefs";
 const PREF_KEY_WRAP_MODE = (gameId: string) => `${gameId}/wrap-mode`;
+const PREF_KEY_LAST_VIEWED_TURN = (gameId: string) =>
+	`${gameId}/last-viewed-turn`;
+
+const HISTORY_NAMESPACE = "game-history";
+const HISTORY_KEY_TURN = (gameId: string, turn: number) =>
+	`${gameId}/turn/${turn}`;
 
 /**
  * GAME_STATE_CONTEXT_KEY is the Svelte context key the in-game shell
@@ -53,9 +59,30 @@ export class GameStateStore {
 	 * game (lifted from the lobby record on `setGame`). Phase 14
 	 * exposes it so the layout can pass it to
 	 * `OrderDraftStore.hydrateFromServer` after both stores boot;
-	 * later phases (history mode, calc) will read it directly.
+	 * Phase 26 keeps the "authoritative server-side turn" meaning —
+	 * only `setGame`, `advanceToPending`, and the visibility-listener
+	 * lobby re-query update it. History navigation (`viewTurn`) leaves
+	 * it alone so the "Return to current turn" affordance keeps a
+	 * reliable target.
 	 */
 	currentTurn = $state(0);
+	/**
+	 * viewedTurn is the turn whose snapshot is currently displayed.
+	 * In live mode it equals `currentTurn`. Phase 26 history mode
+	 * decouples the two: `viewTurn(N)` flips this rune (and `report`)
+	 * to N without touching `currentTurn` or `last-viewed-turn`.
+	 */
+	viewedTurn = $state(0);
+	/**
+	 * historyMode is the derived "user is viewing a past turn" rune
+	 * consumed by Phase 12 sidebar / bottom-tabs wiring, the Phase 26
+	 * history banner, the rendered-report overlay short-circuit, and
+	 * the order-draft mutation gate. It depends only on the rune state
+	 * above, so every consumer reacts to a single source of truth.
+	 */
+	historyMode = $derived(
+		this.status === "ready" && this.viewedTurn < this.currentTurn,
+	);
 	/**
 	 * synthetic is set by `initSynthetic` for DEV-only sessions backed
 	 * by a hand-loaded report (lobby's "Load synthetic report"
@@ -66,6 +93,17 @@ export class GameStateStore {
 	 * this flag is enough to keep the network silent.
 	 */
 	synthetic = $state(false);
+	/**
+	 * pendingTurn carries the latest server-side turn the user has not
+	 * yet opened: it is `> currentTurn` whenever the server reports a
+	 * new turn (either through a `game.turn.ready` push event after
+	 * boot, or through the boot-time discovery that the persisted
+	 * `lastViewedTurn` is behind the lobby's `current_turn`). The
+	 * layout's `$effect` renders a toast/banner when it is non-null;
+	 * `advanceToPending()` refreshes the store onto the new turn and
+	 * clears the rune.
+	 */
+	pendingTurn: number | null = $state(null);
 
 	private client: GalaxyClient | null = null;
 	private cache: Cache | null = null;
@@ -98,12 +136,21 @@ export class GameStateStore {
 		if (this.client === null || this.cache === null) {
 			throw new Error("game-state: setGame called before init");
 		}
+		// Only forget the pending indicator when the consumer is
+		// actually switching games. On the initial `setGame` after
+		// `init` the previous `gameId` is the empty string, and a
+		// concurrent `markPendingTurn` from a push event arriving
+		// while we were still bootstrapping must not be erased.
+		if (this.gameId !== "" && this.gameId !== gameId) {
+			this.pendingTurn = null;
+		}
 		this.gameId = gameId;
 		this.status = "loading";
 		this.error = null;
 		this.report = null;
 
 		this.wrapMode = await readWrapMode(this.cache, gameId);
+		const lastViewed = await readLastViewedTurn(this.cache, gameId);
 
 		try {
 			const summary = await this.findGame(gameId);
@@ -114,7 +161,23 @@ export class GameStateStore {
 			}
 			this.gameName = summary.gameName;
 			this.currentTurn = summary.currentTurn;
-			await this.loadTurn(summary.currentTurn);
+			// If the persisted last-viewed turn is older than the
+			// server-side current turn, open the user on their last-seen
+			// snapshot and surface the gap through `pendingTurn` so the
+			// shell can render a "new turn available" affordance instead
+			// of silently auto-advancing. After Phase 26 the same gap
+			// also flips `historyMode` to true (viewedTurn < currentTurn),
+			// so the read-only banner appears alongside the toast.
+			if (
+				lastViewed !== null &&
+				lastViewed >= 0 &&
+				lastViewed < summary.currentTurn
+			) {
+				this.pendingTurn = summary.currentTurn;
+				await this.loadTurn(lastViewed, { isCurrent: false });
+			} else {
+				await this.loadTurn(summary.currentTurn, { isCurrent: true });
+			}
 		} catch (err) {
 			if (this.destroyed) return;
 			this.status = "error";
@@ -123,29 +186,104 @@ export class GameStateStore {
 	}
 
 	/**
-	 * setTurn loads a different turn snapshot — used by Phase 26 history
-	 * mode. The current turn stays at whatever `setGame` discovered;
-	 * calling without an argument refetches the same turn.
+	 * markPendingTurn records a server-reported new turn (typically
+	 * delivered through `game.turn.ready`). Values that are not
+	 * strictly ahead of the latest known turn (current or already
+	 * pending) are ignored so a replayed event cannot regress the
+	 * indicator.
 	 */
-	async setTurn(turn: number): Promise<void> {
-		if (this.client === null) return;
+	markPendingTurn(turn: number): void {
+		const latest = this.pendingTurn ?? this.currentTurn;
+		if (turn > latest) {
+			this.pendingTurn = turn;
+		}
+	}
+
+	/**
+	 * advanceToPending re-queries the lobby record and loads the
+	 * report at the server's latest `current_turn`, then clears the
+	 * pending indicator. Unlike `setGame`, this skips the
+	 * `lastViewedTurn` lookup — the user has explicitly asked to
+	 * jump to the new turn, so any persisted bookmark from the
+	 * previous session is irrelevant. Failures keep the indicator
+	 * set so the user can retry from the same affordance.
+	 */
+	async advanceToPending(): Promise<void> {
+		if (this.pendingTurn === null || this.client === null) {
+			return;
+		}
 		this.status = "loading";
 		this.error = null;
 		try {
-			await this.loadTurn(turn);
+			const summary = await this.findGame(this.gameId);
+			if (summary === null) {
+				this.status = "error";
+				this.error = `game ${this.gameId} is not in your list`;
+				return;
+			}
+			this.gameName = summary.gameName;
+			this.currentTurn = summary.currentTurn;
+			await this.loadTurn(summary.currentTurn, { isCurrent: true });
+			this.pendingTurn = null;
 		} catch (err) {
+			if (this.destroyed) return;
 			this.status = "error";
 			this.error = describe(err);
 		}
 	}
 
 	/**
-	 * refresh re-fetches the report at the current turn. Called on
-	 * window `visibilitychange` so the map and the turn counter stay
-	 * fresh after the user returns to the tab.
+	 * viewTurn loads the historical snapshot for `turn` and switches the
+	 * UI into history mode (Phase 26). The current turn is untouched —
+	 * `historyMode` flips on automatically through the derived rune, and
+	 * the `last-viewed-turn` cache is only refreshed when the caller
+	 * happens to ask for the currentTurn (e.g. `returnToCurrent`). A
+	 * cache hit on `game-history/{gameId}/turn/{N}` skips the network;
+	 * past turns are immutable so the cache never goes stale.
 	 */
-	refresh(): Promise<void> {
-		return this.setTurn(this.currentTurn);
+	async viewTurn(turn: number): Promise<void> {
+		if (this.client === null) return;
+		if (!Number.isFinite(turn) || turn < 0 || turn > this.currentTurn) {
+			return;
+		}
+		this.status = "loading";
+		this.error = null;
+		try {
+			await this.loadTurn(turn, { isCurrent: turn === this.currentTurn });
+		} catch (err) {
+			if (this.destroyed) return;
+			this.status = "error";
+			this.error = describe(err);
+		}
+	}
+
+	/**
+	 * returnToCurrent jumps back to the server's current turn after a
+	 * history excursion. Thin wrapper around `viewTurn(currentTurn)` so
+	 * the banner / popover share the same call site.
+	 */
+	returnToCurrent(): Promise<void> {
+		return this.viewTurn(this.currentTurn);
+	}
+
+	/**
+	 * refresh is fired from the `visibilitychange` listener. In live
+	 * mode it re-fetches the report at the current turn so the map and
+	 * the counter catch up after the user returns to the tab. In
+	 * history mode it is a no-op: the user is intentionally viewing a
+	 * past turn, push events (Phase 24) deliver new-turn notifications
+	 * asynchronously, and forcing a reload would silently bump the
+	 * user out of history mode.
+	 */
+	async refresh(): Promise<void> {
+		if (this.client === null) return;
+		if (this.historyMode) return;
+		try {
+			await this.loadTurn(this.currentTurn, { isCurrent: true });
+		} catch (err) {
+			if (this.destroyed) return;
+			console.warn("game-state: refresh failed", err);
+		}
 	}
 
 	/**
@@ -193,6 +331,7 @@ export class GameStateStore {
 		this.wrapMode = await readWrapMode(opts.cache, opts.gameId);
 		this.report = opts.report;
 		this.currentTurn = opts.report.turn;
+		this.viewedTurn = opts.report.turn;
 		this.status = "ready";
 	}
 
@@ -212,13 +351,57 @@ export class GameStateStore {
 		return games.find((g) => g.gameId === gameId) ?? null;
 	}
 
-	private async loadTurn(turn: number): Promise<void> {
+	private async loadTurn(
+		turn: number,
+		opts: { isCurrent: boolean },
+	): Promise<void> {
 		if (this.client === null) return;
-		const report = await fetchGameReport(this.client, this.gameId, turn);
+		const report = await this.readReport(turn, opts.isCurrent);
 		if (this.destroyed) return;
 		this.report = report;
-		this.currentTurn = turn;
+		this.viewedTurn = turn;
 		this.status = "ready";
+		if (this.cache === null) return;
+		if (opts.isCurrent) {
+			// Persist last-viewed-turn only when the user is caught up
+			// on the live snapshot. Historical excursions are ephemeral
+			// (Phase 26 decision): the resume-on-open affordance from
+			// Phase 11 must keep meaning "the latest turn this player
+			// was caught up on", not "wherever they last clicked".
+			await this.cache.put(
+				PREF_NAMESPACE,
+				PREF_KEY_LAST_VIEWED_TURN(this.gameId),
+				turn,
+			);
+			return;
+		}
+		// Past turns are immutable, so the snapshot is safe to cache
+		// for fast re-entry. The current-turn snapshot deliberately
+		// skips the cache — it is mutable until the next tick.
+		await this.cache.put(
+			HISTORY_NAMESPACE,
+			HISTORY_KEY_TURN(this.gameId, turn),
+			report,
+		);
+	}
+
+	private async readReport(
+		turn: number,
+		isCurrent: boolean,
+	): Promise<GameReport> {
+		if (this.client === null) {
+			throw new Error("game-state: readReport called without client");
+		}
+		if (!isCurrent && this.cache !== null) {
+			const cached = await this.cache.get<GameReport>(
+				HISTORY_NAMESPACE,
+				HISTORY_KEY_TURN(this.gameId, turn),
+			);
+			if (cached !== undefined && cached.turn === turn) {
+				return cached;
+			}
+		}
+		return await fetchGameReport(this.client, this.gameId, turn);
 	}
 
 	private installVisibilityListener(): void {
@@ -239,6 +422,20 @@ async function readWrapMode(cache: Cache, gameId: string): Promise<WrapMode> {
 	return "torus";
 }
 
+async function readLastViewedTurn(
+	cache: Cache,
+	gameId: string,
+): Promise<number | null> {
+	const stored = await cache.get<number>(
+		PREF_NAMESPACE,
+		PREF_KEY_LAST_VIEWED_TURN(gameId),
+	);
+	if (typeof stored !== "number" || !Number.isFinite(stored)) {
+		return null;
+	}
+	return stored;
+}
+
 function describe(err: unknown): string {
 	if (err instanceof GameStateError) {
 		return err.message;

ui/frontend/src/lib/header/header.svelte

@@ -1,8 +1,10 @@
 <!--
 Top header for the in-game shell. Composes the in-game ID strip
-(race name @ game name, turn N), view dropdown / hamburger, and the
-account menu. The sidebar-toggle slot to its left appears only on
-tablet viewports (768–1024 px) and is wired by `+layout.svelte`.
+(race name @ game name) followed by the Phase 26 turn navigator (a
+`← Turn N →` triplet with a popover of every turn), the view
+dropdown / hamburger, and the account menu. The sidebar-toggle slot
+to its left appears only on tablet viewports (768–1024 px) and is
+wired by `+layout.svelte`.
 
 The race name is read from the engine's `Report.race`, the game
 name from the lobby's `GameSummary.gameName`. While either piece
@@ -22,6 +24,7 @@ absent until Phase 24 wires push-event state.
 	} from "$lib/game-state.svelte";
 	import ViewMenu from "./view-menu.svelte";
 	import AccountMenu from "./account-menu.svelte";
+	import TurnNavigator from "./turn-navigator.svelte";
 
 	type Props = {
 		gameId: string;
@@ -44,27 +47,14 @@ absent until Phase 24 wires push-event state.
 		const name = gameState?.gameName ?? "";
 		return name === "" ? i18n.t("game.shell.unknown") : name;
 	});
-	const turn = $derived.by(() => {
-		const report = gameState?.report;
-		return report === null || report === undefined
-			? i18n.t("game.shell.unknown")
-			: String(report.turn);
-	});
-
-	const headline = $derived(
-		i18n.t("game.shell.headline", {
-			race: raceName,
-			game: gameName,
-			turn,
-		}),
-	);
 </script>
 
 <header class="game-shell-header" data-testid="game-shell-header">
-	<div class="left">
-		<span class="headline" data-testid="game-shell-headline">
-			{headline}
+	<div class="left" data-testid="game-shell-headline">
+		<span class="identity" data-testid="game-shell-identity">
+			{raceName} @ {gameName}
 		</span>
+		<TurnNavigator />
 	</div>
 	<div class="right">
 		<button
@@ -106,7 +96,7 @@ absent until Phase 24 wires push-event state.
 		gap: 0.75rem;
 		min-width: 0;
 	}
-	.headline {
+	.identity {
 		font-weight: 500;
 		white-space: nowrap;
 		overflow: hidden;

ui/frontend/src/lib/header/history-banner.svelte

@@ -0,0 +1,80 @@
+<!--
+Phase 26 read-only banner. Renders directly under the shell header
+whenever the user is viewing a past turn (`gameState.historyMode`).
+Carries the turn number and a "Return to current turn" action that
+delegates to `gameState.returnToCurrent()`. The banner is invisible
+in live mode so the active-view chrome keeps its full vertical
+budget.
+-->
+<script lang="ts">
+	import { getContext } from "svelte";
+	import { i18n } from "$lib/i18n/index.svelte";
+	import {
+		GAME_STATE_CONTEXT_KEY,
+		type GameStateStore,
+	} from "$lib/game-state.svelte";
+
+	const gameState = getContext<GameStateStore | undefined>(
+		GAME_STATE_CONTEXT_KEY,
+	);
+
+	const viewedTurn = $derived(gameState?.viewedTurn ?? 0);
+	const visible = $derived(gameState?.historyMode === true);
+
+	function onReturn(): void {
+		void gameState?.returnToCurrent();
+	}
+</script>
+
+{#if visible}
+	<aside class="history-banner" data-testid="history-banner" role="status">
+		<span class="message">
+			{i18n.t("game.shell.history.viewing", { turn: String(viewedTurn) })}
+		</span>
+		<button
+			type="button"
+			class="return"
+			data-testid="history-banner-return"
+			onclick={onReturn}
+		>
+			{i18n.t("game.shell.history.return_to_current")}
+		</button>
+	</aside>
+{/if}
+
+<style>
+	.history-banner {
+		position: sticky;
+		top: 3rem;
+		z-index: 35;
+		display: flex;
+		align-items: center;
+		gap: 0.75rem;
+		padding: 0.4rem 0.9rem;
+		background: #2a2438;
+		color: #efe9c8;
+		border-bottom: 1px solid #45375a;
+		font-family: system-ui, sans-serif;
+		font-size: 0.9rem;
+	}
+	.message {
+		flex: 1;
+		min-width: 0;
+		overflow: hidden;
+		text-overflow: ellipsis;
+		white-space: nowrap;
+	}
+	.return {
+		font: inherit;
+		padding: 0.25rem 0.65rem;
+		background: transparent;
+		color: inherit;
+		border: 1px solid #6c5a8a;
+		border-radius: 4px;
+		cursor: pointer;
+		white-space: nowrap;
+	}
+	.return:hover {
+		background: #3a3050;
+	}
+</style>

ui/frontend/src/lib/header/turn-navigator.svelte

@@ -0,0 +1,263 @@
+<!--
+Phase 26 header turn navigator. Replaces the Phase 11 inline turn
+number with a `← Turn N →` triplet. The arrows step ±1 (disabled at
+boundaries `0` and `currentTurn`), the middle button opens a popover
+listing every turn `Turn #0`…`Turn #currentTurn` with the current row
+tagged. No free-text input — every reachable turn is in the list, so
+there is nothing to validate.
+
+Desktop and mobile share the same component: an absolute-positioned
+popover anchored to the trigger on desktop becomes a fixed full-width
+drawer below the 768 px breakpoint, mirroring `view-menu.svelte`.
+
+Selecting a row calls `gameState.viewTurn(N)`; the row that matches
+`currentTurn` delegates to `gameState.returnToCurrent()` so the
+"leave history" path always flows through one method.
+-->
+<script lang="ts">
+	import { getContext, onMount } from "svelte";
+	import { i18n } from "$lib/i18n/index.svelte";
+	import {
+		GAME_STATE_CONTEXT_KEY,
+		type GameStateStore,
+	} from "$lib/game-state.svelte";
+
+	const gameState = getContext<GameStateStore | undefined>(
+		GAME_STATE_CONTEXT_KEY,
+	);
+
+	let open = $state(false);
+	let rootEl: HTMLDivElement | null = $state(null);
+
+	const currentTurn = $derived(gameState?.currentTurn ?? 0);
+	const viewedTurn = $derived(gameState?.viewedTurn ?? 0);
+	const ready = $derived(gameState?.status === "ready");
+	const canPrev = $derived(ready && viewedTurn > 0);
+	const canNext = $derived(ready && viewedTurn < currentTurn);
+	// Until the boot completes the store has no report, so the
+	// counter falls back to the same `?` placeholder Phase 11 used in
+	// the static headline. Avoids briefly flashing `turn 0` while the
+	// lobby / report calls are in flight.
+	const turnText = $derived(
+		ready ? String(viewedTurn) : i18n.t("game.shell.unknown"),
+	);
+
+	// Descending list newest → oldest. The popover stays compact for
+	// short games and scrolls for long ones; the current-turn row is
+	// pinned at the top with an explicit badge so the affordance to
+	// jump back is always reachable without scrolling.
+	const turns = $derived.by(() => {
+		if (!ready) return [] as number[];
+		const out: number[] = [];
+		for (let i = currentTurn; i >= 0; i--) {
+			out.push(i);
+		}
+		return out;
+	});
+
+	function toggleOpen(): void {
+		if (!ready) return;
+		open = !open;
+	}
+
+	async function goToTurn(turn: number): Promise<void> {
+		open = false;
+		if (gameState === undefined) return;
+		if (turn === gameState.currentTurn) {
+			await gameState.returnToCurrent();
+			return;
+		}
+		await gameState.viewTurn(turn);
+	}
+
+	async function step(delta: number): Promise<void> {
+		if (gameState === undefined) return;
+		const next = viewedTurn + delta;
+		if (next < 0 || next > currentTurn) return;
+		if (next === gameState.currentTurn) {
+			await gameState.returnToCurrent();
+			return;
+		}
+		await gameState.viewTurn(next);
+	}
+
+	function onKeyDown(event: KeyboardEvent): void {
+		if (event.key === "Escape" && open) {
+			open = false;
+		}
+	}
+
+	onMount(() => {
+		const handleClick = (event: MouseEvent): void => {
+			if (!open || rootEl === null) return;
+			const target = event.target;
+			if (target instanceof Node && rootEl.contains(target)) return;
+			open = false;
+		};
+		document.addEventListener("click", handleClick, true);
+		document.addEventListener("keydown", onKeyDown);
+		return () => {
+			document.removeEventListener("click", handleClick, true);
+			document.removeEventListener("keydown", onKeyDown);
+		};
+	});
+</script>
+
+<div class="turn-navigator" bind:this={rootEl} data-testid="turn-navigator">
+	<button
+		type="button"
+		class="step"
+		data-testid="turn-navigator-prev"
+		aria-label={i18n.t("game.shell.turn.prev")}
+		disabled={!canPrev}
+		onclick={() => void step(-1)}
+	>
+		←
+	</button>
+	<button
+		type="button"
+		class="trigger"
+		data-testid="turn-navigator-trigger"
+		aria-haspopup="menu"
+		aria-expanded={open}
+		aria-label={open
+			? i18n.t("game.shell.turn.close_navigator")
+			: i18n.t("game.shell.turn.open_navigator")}
+		disabled={!ready}
+		onclick={toggleOpen}
+	>
+		{i18n.t("game.shell.turn.label", { turn: turnText })}
+	</button>
+	<button
+		type="button"
+		class="step"
+		data-testid="turn-navigator-next"
+		aria-label={i18n.t("game.shell.turn.next")}
+		disabled={!canNext}
+		onclick={() => void step(1)}
+	>
+		→
+	</button>
+	{#if open}
+		<div class="surface" role="menu" data-testid="turn-navigator-list">
+			{#each turns as turn (turn)}
+				<button
+					type="button"
+					role="menuitem"
+					class="row"
+					class:viewed={turn === viewedTurn}
+					data-testid={`turn-navigator-item-${turn}`}
+					onclick={() => void goToTurn(turn)}
+				>
+					<span class="label">
+						{i18n.t("game.shell.turn.list_item", { turn: String(turn) })}
+					</span>
+					{#if turn === currentTurn}
+						<span class="badge" data-testid="turn-navigator-current-badge">
+							{i18n.t("game.shell.history.current_badge")}
+						</span>
+					{/if}
+				</button>
+			{/each}
+		</div>
+	{/if}
+</div>
+
+<style>
+	.turn-navigator {
+		position: relative;
+		display: inline-flex;
+		align-items: stretch;
+		gap: 0.25rem;
+	}
+	.step,
+	.trigger {
+		font: inherit;
+		font-size: 1rem;
+		padding: 0.25rem 0.55rem;
+		background: transparent;
+		color: inherit;
+		border: 1px solid #2a3150;
+		border-radius: 4px;
+		cursor: pointer;
+		line-height: 1;
+	}
+	.step:hover:not(:disabled),
+	.trigger:hover:not(:disabled) {
+		background: #1c2238;
+	}
+	.step:disabled,
+	.trigger:disabled {
+		opacity: 0.4;
+		cursor: not-allowed;
+	}
+	.trigger {
+		min-width: 5rem;
+		font-weight: 500;
+	}
+	.surface {
+		position: absolute;
+		top: calc(100% + 0.25rem);
+		left: 0;
+		min-width: 10rem;
+		max-height: 18rem;
+		overflow-y: auto;
+		display: flex;
+		flex-direction: column;
+		background: #14182a;
+		border: 1px solid #2a3150;
+		border-radius: 6px;
+		box-shadow: 0 6px 18px rgba(0, 0, 0, 0.4);
+		z-index: 50;
+	}
+	.row {
+		display: flex;
+		align-items: center;
+		justify-content: space-between;
+		gap: 0.75rem;
+		text-align: left;
+		font: inherit;
+		padding: 0.4rem 0.75rem;
+		background: transparent;
+		color: inherit;
+		border: 0;
+		cursor: pointer;
+	}
+	.row:hover {
+		background: #1c2238;
+	}
+	.row.viewed {
+		font-weight: 600;
+		background: #1a2040;
+	}
+	.label {
+		flex: 1;
+		min-width: 0;
+		overflow: hidden;
+		text-overflow: ellipsis;
+		white-space: nowrap;
+	}
+	.badge {
+		flex: 0 0 auto;
+		font-size: 0.75rem;
+		text-transform: uppercase;
+		letter-spacing: 0.04em;
+		padding: 0.05rem 0.4rem;
+		background: #2a3150;
+		color: #d8def0;
+		border-radius: 999px;
+	}
+	@media (max-width: 767.98px) {
+		.surface {
+			position: fixed;
+			top: 3rem;
+			right: 0;
+			left: 0;
+			min-width: 0;
+			max-height: calc(100vh - 3rem);
+			border-radius: 0;
+			border-left: 0;
+			border-right: 0;
+		}
+	}
+</style>

ui/frontend/src/lib/i18n/locales/en.ts

@@ -7,10 +7,15 @@
 const en = {
 	"common.language": "language",
 	"common.loading": "loading…",
+	"common.dismiss": "dismiss",
 	"common.browser_not_supported_title": "browser not supported",
 	"common.browser_not_supported_body":
 		"Galaxy requires Ed25519 in WebCrypto. See supported browsers.",
 
+	"game.events.turn_ready.message": "turn {turn} is ready",
+	"game.events.turn_ready.action": "view now",
+	"game.events.signature_failed": "verification failed, reconnecting…",
+
 	"login.title": "sign in to Galaxy",
 	"login.email_label": "email",
 	"login.email_required": "email must not be empty",
@@ -84,7 +89,6 @@ const en = {
 	"lobby.error.unknown": "{message}",
 
 	"game.shell.unknown": "?",
-	"game.shell.headline": "{race} @ {game}, turn {turn}",
 	"game.shell.connection.online": "online",
 	"game.shell.connection.reconnecting": "reconnecting…",
 	"game.shell.connection.offline": "offline",
@@ -99,6 +103,15 @@ const en = {
 	"game.shell.menu.language": "language",
 	"game.shell.menu.logout": "logout",
 	"game.shell.coming_soon": "coming soon",
+	"game.shell.turn.label": "turn {turn}",
+	"game.shell.turn.list_item": "turn #{turn}",
+	"game.shell.turn.prev": "previous turn",
+	"game.shell.turn.next": "next turn",
+	"game.shell.turn.open_navigator": "open turn list",
+	"game.shell.turn.close_navigator": "close turn list",
+	"game.shell.history.viewing": "Viewing turn {turn} · read-only",
+	"game.shell.history.return_to_current": "Return to current turn",
+	"game.shell.history.current_badge": "current",
 	"game.view.map": "map",
 	"game.view.table": "table",
 	"game.view.table.planets": "planets",
@@ -123,13 +136,20 @@ const en = {
 	"game.sidebar.order.sync.in_flight": "syncing…",
 	"game.sidebar.order.sync.synced": "synced with server",
 	"game.sidebar.order.sync.error": "sync failed: {message}",
+	"game.sidebar.order.sync.offline": "queued — offline, will retry on reconnect",
+	"game.sidebar.order.sync.conflict": "turn closed before submit",
+	"game.sidebar.order.sync.paused": "game paused — orders disabled",
 	"game.sidebar.order.sync.retry": "retry",
+	"game.sidebar.order.conflict.banner": "Turn {turn} closed before your order was accepted. Edit and resubmit.",
+	"game.sidebar.order.conflict.banner_no_turn": "Turn closed before your order was accepted. Edit and resubmit.",
+	"game.sidebar.order.paused.banner": "Game paused. Orders are not accepted until it resumes.",
 	"game.sidebar.order.status.draft": "draft",
 	"game.sidebar.order.status.valid": "valid",
 	"game.sidebar.order.status.invalid": "invalid",
 	"game.sidebar.order.status.submitting": "submitting",
 	"game.sidebar.order.status.applied": "applied",
 	"game.sidebar.order.status.rejected": "rejected",
+	"game.sidebar.order.status.conflict": "conflict",
 	"game.sidebar.order.label.placeholder": "{label}",
 	"game.sidebar.order.label.planet_rename": "rename planet {planet} → {name}",
 	"game.sidebar.order.label.planet_production": "set production on planet {planet} → {target}",
@@ -463,6 +483,27 @@ const en = {
 	"game.report.section.battles.title": "battles",
 	"game.report.section.battles.empty": "no battles last turn",
 	"game.report.section.battles.id_label": "battle",
+	"game.battle.title": "battle",
+	"game.battle.header_title": "Battle on planet {planet_name} (#{planet_number})",
+	"game.battle.loading": "loading battle…",
+	"game.battle.not_found": "battle not found",
+	"game.battle.back_to_report": "back to report",
+	"game.battle.back_to_map": "back to map",
+	"game.battle.controls.play": "play",
+	"game.battle.controls.pause": "pause",
+	"game.battle.controls.step_forward": "step forward",
+	"game.battle.controls.step_backward": "step back",
+	"game.battle.controls.rewind": "rewind to start",
+	"game.battle.controls.speed_label": "speed",
+	"game.battle.controls.speed_1x": "1x",
+	"game.battle.controls.speed_2x": "2x",
+	"game.battle.controls.speed_4x": "4x",
+	"game.battle.controls.speed_6x": "6x",
+	"game.battle.controls.scrub": "scrub battle timeline",
+	"game.battle.controls.log_toggle": "Log",
+	"game.battle.log.destroyed": "{attacker_race}'s {attacker_class} destroyed {defender_race}'s {defender_class}",
+	"game.battle.log.shielded": "{attacker_race}'s {attacker_class} hit {defender_race}'s {defender_class}, shields held",
+	"game.battle.accessibility.protocol_heading": "battle log",
 	"game.report.section.bombings.title": "bombings",
 	"game.report.section.bombings.empty": "no bombings last turn",
 	"game.report.section.bombings.column.planet": "planet",

ui/frontend/src/lib/i18n/locales/ru.ts

@@ -8,10 +8,15 @@ import type en from "./en";
 const ru: Record<keyof typeof en, string> = {
 	"common.language": "язык",
 	"common.loading": "загрузка…",
+	"common.dismiss": "закрыть",
 	"common.browser_not_supported_title": "браузер не поддерживается",
 	"common.browser_not_supported_body":
 		"Galaxy требует поддержки Ed25519 в WebCrypto. См. список поддерживаемых браузеров.",
 
+	"game.events.turn_ready.message": "ход {turn} готов",
+	"game.events.turn_ready.action": "открыть",
+	"game.events.signature_failed": "подпись повреждена, переподключение…",
+
 	"login.title": "вход в Galaxy",
 	"login.email_label": "электронная почта",
 	"login.email_required": "адрес не должен быть пустым",
@@ -85,7 +90,6 @@ const ru: Record<keyof typeof en, string> = {
 	"lobby.error.unknown": "{message}",
 
 	"game.shell.unknown": "?",
-	"game.shell.headline": "{race} @ {game}, ход {turn}",
 	"game.shell.connection.online": "онлайн",
 	"game.shell.connection.reconnecting": "переподключение…",
 	"game.shell.connection.offline": "офлайн",
@@ -100,6 +104,15 @@ const ru: Record<keyof typeof en, string> = {
 	"game.shell.menu.language": "язык",
 	"game.shell.menu.logout": "выйти",
 	"game.shell.coming_soon": "скоро будет",
+	"game.shell.turn.label": "ход {turn}",
+	"game.shell.turn.list_item": "ход #{turn}",
+	"game.shell.turn.prev": "предыдущий ход",
+	"game.shell.turn.next": "следующий ход",
+	"game.shell.turn.open_navigator": "открыть список ходов",
+	"game.shell.turn.close_navigator": "закрыть список ходов",
+	"game.shell.history.viewing": "Просмотр хода {turn} · только чтение",
+	"game.shell.history.return_to_current": "Вернуться к текущему ходу",
+	"game.shell.history.current_badge": "текущий",
 	"game.view.map": "карта",
 	"game.view.table": "таблица",
 	"game.view.table.planets": "планеты",
@@ -124,13 +137,20 @@ const ru: Record<keyof typeof en, string> = {
 	"game.sidebar.order.sync.in_flight": "синхронизация…",
 	"game.sidebar.order.sync.synced": "сохранено на сервере",
 	"game.sidebar.order.sync.error": "ошибка синхронизации: {message}",
+	"game.sidebar.order.sync.offline": "очередь — нет связи, повторим при восстановлении",
+	"game.sidebar.order.sync.conflict": "ход закрылся до отправки",
+	"game.sidebar.order.sync.paused": "игра на паузе — приказы не принимаются",
 	"game.sidebar.order.sync.retry": "повторить",
+	"game.sidebar.order.conflict.banner": "Ход {turn} закрылся до того, как приказ был принят. Отредактируй и отправь ещё раз.",
+	"game.sidebar.order.conflict.banner_no_turn": "Ход закрылся до того, как приказ был принят. Отредактируй и отправь ещё раз.",
+	"game.sidebar.order.paused.banner": "Игра на паузе. Приказы не принимаются, пока она не возобновится.",
 	"game.sidebar.order.status.draft": "черновик",
 	"game.sidebar.order.status.valid": "готова",
 	"game.sidebar.order.status.invalid": "ошибка",
 	"game.sidebar.order.status.submitting": "отправка",
 	"game.sidebar.order.status.applied": "принята",
 	"game.sidebar.order.status.rejected": "отклонена",
+	"game.sidebar.order.status.conflict": "конфликт",
 	"game.sidebar.order.label.placeholder": "{label}",
 	"game.sidebar.order.label.planet_rename": "переименовать планету {planet} → {name}",
 	"game.sidebar.order.label.planet_production": "сменить производство планеты {planet} → {target}",
@@ -464,6 +484,27 @@ const ru: Record<keyof typeof en, string> = {
 	"game.report.section.battles.title": "сражения",
 	"game.report.section.battles.empty": "сражений в этом ходу не было",
 	"game.report.section.battles.id_label": "сражение",
+	"game.battle.title": "сражение",
+	"game.battle.header_title": "Битва на планете {planet_name} (#{planet_number})",
+	"game.battle.controls.speed_6x": "6x",
+	"game.battle.controls.scrub": "перемотать таймлайн битвы",
+	"game.battle.controls.log_toggle": "Лог",
+	"game.battle.loading": "загрузка сражения…",
+	"game.battle.not_found": "сражение не найдено",
+	"game.battle.back_to_report": "к отчёту",
+	"game.battle.back_to_map": "к карте",
+	"game.battle.controls.play": "запустить",
+	"game.battle.controls.pause": "пауза",
+	"game.battle.controls.step_forward": "шаг вперёд",
+	"game.battle.controls.step_backward": "шаг назад",
+	"game.battle.controls.rewind": "к началу",
+	"game.battle.controls.speed_label": "скорость",
+	"game.battle.controls.speed_1x": "1x",
+	"game.battle.controls.speed_2x": "2x",
+	"game.battle.controls.speed_4x": "4x",
+	"game.battle.log.destroyed": "{attacker_class} расы {attacker_race} уничтожает {defender_class} расы {defender_race}",
+	"game.battle.log.shielded": "{attacker_class} расы {attacker_race} попадает в {defender_class} расы {defender_race}, щиты выдержали",
+	"game.battle.accessibility.protocol_heading": "протокол сражения",
 	"game.report.section.bombings.title": "бомбардировки",
 	"game.report.section.bombings.empty": "бомбардировок в этом ходу не было",
 	"game.report.section.bombings.column.planet": "планета",

ui/frontend/src/lib/rendered-report.svelte.ts

@@ -37,6 +37,12 @@ export interface RenderedReportSource {
  * underlying `$state` accesses inside `applyOrderOverlay`, so any
  * change to the report or the draft re-runs every dependent
  * `$derived` block.
+ *
+ * Phase 26: the order draft is composed against the *current* turn,
+ * so projecting it onto a historical snapshot would render fictional
+ * intent on a past report. In history mode the getter returns the
+ * raw server snapshot untouched — the order tab is hidden anyway and
+ * mutations are gated at the store, so nothing else needs to know.
  */
 export function createRenderedReportSource(
 	gameState: GameStateStore,
@@ -46,6 +52,7 @@ export function createRenderedReportSource(
 		get report(): GameReport | null {
 			const raw = gameState.report;
 			if (raw === null) return null;
+			if (gameState.historyMode) return raw;
 			return applyOrderOverlay(raw, orderDraft.commands, orderDraft.statuses);
 		},
 	};

ui/frontend/src/lib/revocation-watcher.ts

@@ -1,157 +0,0 @@
-// `startRevocationWatcher` opens an authenticated SubscribeEvents
-// stream against the gateway and treats any non-aborted termination
-// as a session-revocation signal: the watcher calls
-// `session.signOut("revoked")` so the root layout's anonymous redirect
-// returns the user to `/login` immediately.
-//
-// Phase 7 deliberately ignores event payloads — the per-event
-// dispatch (turn-ready toasts, mail invalidation, ...) lands in
-// Phase 24. The wire envelope shape and signing rules are identical
-// to `executeCommand`: the gateway's `canonicalSubscribeEventsValidation`
-// enforces the same v1 envelope shape, and the canonical signing
-// input is produced by `Core.signRequest`. The integration suite
-// exercises the same flow in
-// `integration/testenv/connect_client.go::SubscribeEvents` with the
-// `gateway.subscribe` literal.
-
-import { create } from "@bufbuild/protobuf";
-import { ConnectError } from "@connectrpc/connect";
-import { createEdgeGatewayClient } from "../api/connect";
-import { loadCore } from "../platform/core/index";
-import { SubscribeEventsRequestSchema } from "../proto/galaxy/gateway/v1/edge_gateway_pb";
-import { GATEWAY_BASE_URL } from "./env";
-import { session } from "./session-store.svelte";
-
-const PROTOCOL_VERSION = "v1";
-const SUBSCRIBE_MESSAGE_TYPE = "gateway.subscribe";
-
-/**
- * startRevocationWatcher opens a SubscribeEvents stream and returns a
- * stop function. Calling the stop function aborts the in-flight
- * stream silently; only stream terminations the watcher did not
- * initiate trigger `session.signOut("revoked")`.
- */
-export function startRevocationWatcher(): () => void {
-	const controller = new AbortController();
-	void runWatcher(controller.signal);
-	return () => controller.abort();
-}
-
-async function runWatcher(signal: AbortSignal): Promise<void> {
-	if (
-		session.status !== "authenticated" ||
-		session.keypair === null ||
-		session.deviceSessionId === null
-	) {
-		return;
-	}
-	const keypair = session.keypair;
-	const deviceSessionId = session.deviceSessionId;
-
-	let stream: AsyncIterable<unknown>;
-	try {
-		const core = await loadCore();
-		const requestId =
-			typeof crypto.randomUUID === "function"
-				? crypto.randomUUID()
-				: fallbackRequestId();
-		const timestampMs = BigInt(Date.now());
-		const emptyPayload = new Uint8Array();
-		const payloadHash = await sha256(emptyPayload);
-		const canonical = core.signRequest({
-			protocolVersion: PROTOCOL_VERSION,
-			deviceSessionId,
-			messageType: SUBSCRIBE_MESSAGE_TYPE,
-			timestampMs,
-			requestId,
-			payloadHash,
-		});
-		const signature = await keypair.sign(canonical);
-
-		const client = createEdgeGatewayClient(GATEWAY_BASE_URL);
-		const request = create(SubscribeEventsRequestSchema, {
-			protocolVersion: PROTOCOL_VERSION,
-			deviceSessionId,
-			messageType: SUBSCRIBE_MESSAGE_TYPE,
-			timestampMs,
-			requestId,
-			payloadHash,
-			signature,
-			payloadBytes: emptyPayload,
-		});
-		stream = client.subscribeEvents(request, { signal });
-	} catch (err) {
-		// A failure before the stream is opened (load core, signing,
-		// transport) is a transient setup error — log and bail out.
-		// Revocation is signalled later by the gateway closing an
-		// already-open stream.
-		if (!signal.aborted) {
-			console.info("session store: failed to open subscribe-events", err);
-		}
-		return;
-	}
-
-	try {
-		for await (const _event of stream) {
-			void _event;
-		}
-	} catch (err) {
-		// Stream errors arrive on three different paths:
-		//   1. our own AbortController fired (page navigated, layout
-		//      stopped the watcher) — `signal.aborted` is true;
-		//   2. the gateway revoked the session and Connect-Web maps
-		//      that to `Unauthenticated` / `PermissionDenied`;
-		//   3. transient network failure (Wi-Fi drop, server
-		//      restart) — anything else.
-		//
-		// Only branch 2 is a true revocation. Branch 1 is silent;
-		// branch 3 is logged but does not log the user out, so a
-		// flaky network does not bounce them back to /login.
-		if (signal.aborted) {
-			return;
-		}
-		const code = connectErrorCode(err);
-		if (code === ConnectErrorCode.Unauthenticated) {
-			await session.signOut("revoked");
-			return;
-		}
-		console.info("session store: subscribe-events stream errored", err);
-		return;
-	}
-	// Clean end-of-stream from the gateway is the documented
-	// `session_invalidation` signal: backend closes the push stream
-	// once the device session flips to revoked.
-	if (!signal.aborted && session.status === "authenticated") {
-		await session.signOut("revoked");
-	}
-}
-
-const ConnectErrorCode = {
-	Canceled: 1,
-	Unauthenticated: 16,
-} as const;
-
-function connectErrorCode(err: unknown): number | null {
-	if (err instanceof ConnectError) {
-		return err.code;
-	}
-	return null;
-}
-
-async function sha256(payload: Uint8Array): Promise<Uint8Array> {
-	const digest = await crypto.subtle.digest(
-		"SHA-256",
-		payload as BufferSource,
-	);
-	return new Uint8Array(digest);
-}
-
-function fallbackRequestId(): string {
-	const buf = new Uint8Array(16);
-	crypto.getRandomValues(buf);
-	let hex = "";
-	for (let i = 0; i < buf.length; i++) {
-		hex += buf[i]!.toString(16).padStart(2, "0");
-	}
-	return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20, 32)}`;
-}

ui/frontend/src/lib/sidebar/order-tab.svelte

@@ -37,6 +37,7 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 		submitting: "game.sidebar.order.status.submitting",
 		applied: "game.sidebar.order.status.applied",
 		rejected: "game.sidebar.order.status.rejected",
+		conflict: "game.sidebar.order.status.conflict",
 	};
 
 	function describe(cmd: OrderCommand): string {
@@ -152,6 +153,32 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 
 <section class="tool" data-testid="sidebar-tool-order">
 	<h3>{i18n.t("game.sidebar.tab.order")}</h3>
+	{#if draft !== undefined && draft.pausedBanner !== null}
+		<div
+			class="banner banner-paused"
+			data-testid="order-paused-banner"
+			data-paused-reason={draft.pausedBanner.reason}
+			role="status"
+		>
+			{i18n.t("game.sidebar.order.paused.banner")}
+		</div>
+	{/if}
+	{#if draft !== undefined && draft.conflictBanner !== null}
+		<div
+			class="banner banner-conflict"
+			data-testid="order-conflict-banner"
+			data-conflict-turn={draft.conflictBanner.turn ?? ""}
+			role="status"
+		>
+			{#if draft.conflictBanner.turn !== null}
+				{i18n.t("game.sidebar.order.conflict.banner", {
+					turn: String(draft.conflictBanner.turn),
+				})}
+			{:else}
+				{i18n.t("game.sidebar.order.conflict.banner_no_turn")}
+			{/if}
+		</div>
+	{/if}
 	{#if draft === undefined || draft.commands.length === 0}
 		<p class="empty" data-testid="order-empty">
 			{i18n.t("game.sidebar.empty.order")}
@@ -202,6 +229,12 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 					{i18n.t("game.sidebar.order.sync.error", {
 						message: draft.syncError ?? "",
 					})}
+				{:else if draft.syncStatus === "offline"}
+					{i18n.t("game.sidebar.order.sync.offline")}
+				{:else if draft.syncStatus === "conflict"}
+					{i18n.t("game.sidebar.order.sync.conflict")}
+				{:else if draft.syncStatus === "paused"}
+					{i18n.t("game.sidebar.order.sync.paused")}
 				{:else}
 					{i18n.t("game.sidebar.order.sync.idle")}
 				{/if}
@@ -286,6 +319,27 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 		color: #6d8cff;
 		border-color: #2f3f6d;
 	}
+	.status-conflict {
+		color: #d99a4b;
+		border-color: #6d4a2f;
+	}
+	.banner {
+		margin: 0 0 0.5rem;
+		padding: 0.5rem 0.75rem;
+		border-radius: 4px;
+		font-size: 0.85rem;
+		line-height: 1.3;
+	}
+	.banner-conflict {
+		color: #f1bf78;
+		background: #2a1f10;
+		border: 1px solid #6d4a2f;
+	}
+	.banner-paused {
+		color: #d4d4d4;
+		background: #1a1f2a;
+		border: 1px solid #2f3f55;
+	}
 	.delete {
 		font: inherit;
 		font-size: 0.85rem;
@@ -317,6 +371,15 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 	.sync-syncing {
 		color: #6d8cff;
 	}
+	.sync-offline {
+		color: #b9a566;
+	}
+	.sync-conflict {
+		color: #d99a4b;
+	}
+	.sync-paused {
+		color: #d4d4d4;
+	}
 	.sync-retry {
 		font: inherit;
 		font-size: 0.8rem;

ui/frontend/src/lib/toast-host.svelte

@@ -0,0 +1,109 @@
+<!--
+Single mounting point for the global toast slot, rendered once from
+the root layout. The host reads `toast.current` reactively and stays
+fully empty (zero DOM nodes inside the wrapper) when no toast is
+active so the surrounding shell layout is not perturbed.
+-->
+<script lang="ts">
+	import { i18n } from "$lib/i18n/index.svelte";
+	import { toast } from "$lib/toast.svelte";
+
+	function handleAction(): void {
+		const current = toast.current;
+		if (current === null) {
+			return;
+		}
+		const action = current.onAction;
+		toast.dismiss(current.id);
+		action?.();
+	}
+
+	function handleClose(): void {
+		if (toast.current === null) {
+			return;
+		}
+		toast.dismiss(toast.current.id);
+	}
+</script>
+
+{#if toast.current !== null}
+	<div class="toast-host" role="status" aria-live="polite">
+		<div class="toast" data-testid="toast">
+			<span class="toast-message" data-testid="toast-message">
+				{i18n.t(toast.current.messageKey, toast.current.messageParams)}
+			</span>
+			{#if toast.current.actionLabelKey !== undefined}
+				<button
+					type="button"
+					class="toast-action"
+					data-testid="toast-action"
+					onclick={handleAction}
+				>
+					{i18n.t(toast.current.actionLabelKey)}
+				</button>
+			{/if}
+			<button
+				type="button"
+				class="toast-close"
+				data-testid="toast-close"
+				aria-label={i18n.t("common.dismiss")}
+				onclick={handleClose}
+			>
+				×
+			</button>
+		</div>
+	</div>
+{/if}
+
+<style>
+	.toast-host {
+		position: fixed;
+		top: 1rem;
+		left: 50%;
+		transform: translateX(-50%);
+		z-index: 1000;
+		max-width: min(28rem, calc(100vw - 2rem));
+	}
+	.toast {
+		display: flex;
+		align-items: center;
+		gap: 0.75rem;
+		padding: 0.6rem 0.85rem;
+		background: #1a2034;
+		color: #e8eaf6;
+		border: 1px solid #2c3354;
+		border-radius: 0.5rem;
+		box-shadow: 0 4px 16px rgba(0, 0, 0, 0.5);
+		font-size: 0.9rem;
+	}
+	.toast-message {
+		flex: 1;
+		min-width: 0;
+	}
+	.toast-action {
+		background: transparent;
+		color: #8ab4f8;
+		border: none;
+		font-weight: 600;
+		cursor: pointer;
+		font-size: 0.8rem;
+		padding: 0.2rem 0.5rem;
+		text-transform: uppercase;
+		letter-spacing: 0.04em;
+	}
+	.toast-action:hover {
+		text-decoration: underline;
+	}
+	.toast-close {
+		background: transparent;
+		color: #94a3b8;
+		border: none;
+		font-size: 1.1rem;
+		line-height: 1;
+		cursor: pointer;
+		padding: 0 0.25rem;
+	}
+	.toast-close:hover {
+		color: #e8eaf6;
+	}
+</style>

ui/frontend/src/lib/toast.svelte.ts

@@ -0,0 +1,97 @@
+// `ToastStore` is the single transient-notification primitive for the
+// SvelteKit shell. Phase 24 ships it together with the push-event
+// dispatch: the per-game layout shows one `Turn N is ready. View now.`
+// toast on a verified `game.turn.ready` event. Later phases reuse the
+// same store for mail / battle / lobby toasts (PLAN.md §"cross-cutting
+// shell").
+//
+// The store keeps **one** active toast at a time: a fresh `show()`
+// replaces the previous descriptor. This matches the UX intent of
+// "one loud notification at a time" — the rare cases where several
+// events arrive in quick succession are still observable, because
+// each replacement re-arms the timer and the user sees every payload
+// in turn.
+
+import type { TranslationKey } from "./i18n/index.svelte";
+
+/**
+ * ToastDescriptor describes one toast in flight. `messageKey` and
+ * `actionLabelKey` are typed against the i18n catalog so a missing
+ * translation key fails at compile time. `durationMs === null` (or
+ * `undefined`) makes the toast sticky — the user must dismiss it
+ * through the action button or another `show()` call.
+ */
+export interface ToastDescriptor {
+	id: string;
+	messageKey: TranslationKey;
+	messageParams?: Record<string, string>;
+	actionLabelKey?: TranslationKey;
+	onAction?: () => void;
+	durationMs?: number | null;
+}
+
+class ToastStore {
+	current: ToastDescriptor | null = $state(null);
+
+	private timer: ReturnType<typeof setTimeout> | null = null;
+	private counter = 0;
+
+	/**
+	 * show replaces the active toast with descriptor and returns its
+	 * fresh id. Pass that id to `dismiss(id)` from a delayed callback
+	 * to avoid dismissing a newer toast that already took its slot.
+	 */
+	show(descriptor: Omit<ToastDescriptor, "id">): string {
+		this.clearTimer();
+		this.counter += 1;
+		const id = String(this.counter);
+		const full: ToastDescriptor = { ...descriptor, id };
+		this.current = full;
+		if (
+			full.durationMs !== null &&
+			full.durationMs !== undefined &&
+			full.durationMs > 0
+		) {
+			const duration = full.durationMs;
+			this.timer = setTimeout(() => {
+				this.dismiss(id);
+			}, duration);
+		}
+		return id;
+	}
+
+	/**
+	 * dismiss clears the active toast. With an id, the call is a
+	 * no-op when the active toast has a different id — this guards
+	 * the auto-dismiss timer from clobbering a newer descriptor.
+	 */
+	dismiss(id?: string): void {
+		if (
+			id !== undefined &&
+			(this.current === null || this.current.id !== id)
+		) {
+			return;
+		}
+		this.clearTimer();
+		this.current = null;
+	}
+
+	/**
+	 * resetForTests forgets every in-flight descriptor and the id
+	 * counter. Production code never calls this.
+	 */
+	resetForTests(): void {
+		this.clearTimer();
+		this.current = null;
+		this.counter = 0;
+	}
+
+	private clearTimer(): void {
+		if (this.timer !== null) {
+			clearTimeout(this.timer);
+			this.timer = null;
+		}
+	}
+}
+
+export const toast = new ToastStore();

ui/frontend/src/map/battle-markers.ts

@@ -0,0 +1,168 @@
+// Phase 27 battle and bombing markers on the map.
+//
+// Two visual markers per planet:
+//
+//   * Battle marker — an X cross drawn through the corners of the
+//     square that circumscribes the planet circle. Two yellow
+//     LinePrim, stroke width scales linearly with the number of
+//     shots: 1 shot → 1px, 100+ shots → 5px (capped). Clicking
+//     either line opens the Battle Viewer for the corresponding
+//     UUID.
+//   * Bombing marker — a thin stroke-only circle slightly larger
+//     than the planet circle. Yellow on damaged planets, red on
+//     wiped planets. Clicking it deep-links to the bombings row in
+//     the Reports view for the planet number.
+//
+// Both markers are wired into `state-binding.ts` so they live in the
+// same `world` / `hitLookup` plumbing as planets and ship groups.
+
+import type { GameReport, ReportPlanet } from "../api/game-state";
+import type {
+	CirclePrim,
+	LinePrim,
+	Primitive,
+	PrimitiveID,
+	Style,
+} from "./world";
+
+export const BATTLE_MARKER_COLOR = 0xffd400;
+export const BOMBING_MARKER_COLOR_DAMAGED = 0xffd400;
+export const BOMBING_MARKER_COLOR_WIPED = 0xff3030;
+
+/** Battle and bombing marker primitive ids use a high-bit prefix to
+ * avoid colliding with planet numbers or cargo-route line ids. */
+export const BATTLE_MARKER_ID_PREFIX = 0xa0000000;
+export const BOMBING_MARKER_ID_PREFIX = 0xc0000000;
+
+const PLANET_RADIUS_WORLD = 6;
+const BOMBING_RING_RADIUS = PLANET_RADIUS_WORLD + 3;
+const BATTLE_CROSS_HALF = PLANET_RADIUS_WORLD + 2;
+
+/** Battle marker priority sits between planets (1..4) and cargo
+ * routes; the cross is over the planet but loses clicks against the
+ * planet glyph itself. */
+const BATTLE_MARKER_PRIORITY = 9;
+const BOMBING_MARKER_PRIORITY = 10;
+
+const BATTLE_LINE_INDEX_A = 0;
+const BATTLE_LINE_INDEX_B = 1;
+
+export interface BattleMarkerTarget {
+	kind: "battle";
+	battleId: string;
+	planet: number;
+}
+
+export interface BombingMarkerTarget {
+	kind: "bombing";
+	planet: number;
+}
+
+export type MarkerTarget = BattleMarkerTarget | BombingMarkerTarget;
+
+export interface BuildMarkersResult {
+	primitives: Primitive[];
+	lookup: Map<PrimitiveID, MarkerTarget>;
+}
+
+/**
+ * battleMarkerStrokeWidth maps a battle's `shots` count to a stroke
+ * width in pixels. 1 shot → 1 px (the thinnest visible), 100+ shots
+ * → 5 px (the cap). Linearly interpolated between those bounds.
+ */
+export function battleMarkerStrokeWidth(shots: number): number {
+	if (shots <= 1) return 1;
+	if (shots >= 100) return 5;
+	return 1 + ((shots - 1) * 4) / 99;
+}
+
+/**
+ * buildBattleAndBombingMarkers emits battle and bombing marker
+ * primitives plus a hit-lookup mapping for the current-turn report.
+ * Battles whose planet is not visible (e.g. observer-only without a
+ * report.planets entry) are skipped — they have no on-map location
+ * to anchor against.
+ */
+export function buildBattleAndBombingMarkers(
+	report: GameReport,
+): BuildMarkersResult {
+	const planetByNumber = new Map<number, ReportPlanet>();
+	for (const planet of report.planets) {
+		planetByNumber.set(planet.number, planet);
+	}
+
+	const primitives: Primitive[] = [];
+	const lookup = new Map<PrimitiveID, MarkerTarget>();
+
+	for (let i = 0; i < report.battles.length; i++) {
+		const battle = report.battles[i];
+		const planet = planetByNumber.get(battle.planet);
+		if (planet === undefined) continue;
+		const strokeWidthPx = battleMarkerStrokeWidth(battle.shots);
+		const style: Style = {
+			strokeColor: BATTLE_MARKER_COLOR,
+			strokeAlpha: 0.95,
+			strokeWidthPx,
+		};
+		const baseId = BATTLE_MARKER_ID_PREFIX | (i << 4);
+		const lineA: LinePrim = {
+			kind: "line",
+			id: baseId | BATTLE_LINE_INDEX_A,
+			priority: BATTLE_MARKER_PRIORITY,
+			style,
+			hitSlopPx: 0,
+			x1: planet.x - BATTLE_CROSS_HALF,
+			y1: planet.y - BATTLE_CROSS_HALF,
+			x2: planet.x + BATTLE_CROSS_HALF,
+			y2: planet.y + BATTLE_CROSS_HALF,
+		};
+		const lineB: LinePrim = {
+			kind: "line",
+			id: baseId | BATTLE_LINE_INDEX_B,
+			priority: BATTLE_MARKER_PRIORITY,
+			style,
+			hitSlopPx: 0,
+			x1: planet.x - BATTLE_CROSS_HALF,
+			y1: planet.y + BATTLE_CROSS_HALF,
+			x2: planet.x + BATTLE_CROSS_HALF,
+			y2: planet.y - BATTLE_CROSS_HALF,
+		};
+		const target: BattleMarkerTarget = {
+			kind: "battle",
+			battleId: battle.id,
+			planet: battle.planet,
+		};
+		primitives.push(lineA, lineB);
+		lookup.set(lineA.id, target);
+		lookup.set(lineB.id, target);
+	}
+
+	for (let i = 0; i < report.bombings.length; i++) {
+		const bombing = report.bombings[i];
+		const planet = planetByNumber.get(bombing.planetNumber);
+		if (planet === undefined) continue;
+		const color = bombing.wiped
+			? BOMBING_MARKER_COLOR_WIPED
+			: BOMBING_MARKER_COLOR_DAMAGED;
+		const style: Style = {
+			strokeColor: color,
+			strokeAlpha: 0.9,
+			strokeWidthPx: 1.5,
+		};
+		const id = BOMBING_MARKER_ID_PREFIX | i;
+		const ring: CirclePrim = {
+			kind: "circle",
+			id,
+			priority: BOMBING_MARKER_PRIORITY,
+			style,
+			hitSlopPx: 0,
+			x: planet.x,
+			y: planet.y,
+			radius: BOMBING_RING_RADIUS,
+		};
+		primitives.push(ring);
+		lookup.set(id, { kind: "bombing", planet: bombing.planetNumber });
+	}
+
+	return { primitives, lookup };
+}

ui/frontend/src/map/state-binding.ts

@@ -15,6 +15,7 @@
 
 import type { GameReport, ReportPlanet } from "../api/game-state";
 import type { ShipGroupRef } from "../lib/selection.svelte";
+import { buildBattleAndBombingMarkers } from "./battle-markers";
 import { shipGroupsToPrimitives } from "./ship-groups";
 import { World, type Primitive, type PrimitiveID, type Style } from "./world";
 
@@ -83,7 +84,9 @@ function priorityFor(kind: ReportPlanet["kind"]): number {
  */
 export type HitTarget =
 	| { kind: "planet"; number: number }
-	| { kind: "shipGroup"; ref: ShipGroupRef };
+	| { kind: "shipGroup"; ref: ShipGroupRef }
+	| { kind: "battle"; battleId: string; planet: number }
+	| { kind: "bombing"; planet: number };
 
 export interface ReportToWorldResult {
 	world: World;
@@ -127,6 +130,14 @@ export function reportToWorld(report: GameReport): ReportToWorldResult {
 		hitLookup.set(primId, { kind: "shipGroup", ref });
 	}
 
+	const markers = buildBattleAndBombingMarkers(report);
+	for (const prim of markers.primitives) {
+		primitives.push(prim);
+	}
+	for (const [primId, target] of markers.lookup) {
+		hitLookup.set(primId, target);
+	}
+
 	const width = report.mapWidth > 0 ? report.mapWidth : 1;
 	const height = report.mapHeight > 0 ? report.mapHeight : 1;
 	return { world: new World(width, height, primitives), hitLookup };

ui/frontend/src/proto/galaxy/fbs/lobby/application-submit-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { ApplicationSummary, ApplicationSummaryT } from './application-summary.js';
+import { ApplicationSummary, ApplicationSummaryT } from '../lobby/application-summary.js';
 
 
 export class ApplicationSubmitResponse implements flatbuffers.IUnpackableObject<ApplicationSubmitResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/error-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { ErrorBody, ErrorBodyT } from './error-body.js';
+import { ErrorBody, ErrorBodyT } from '../lobby/error-body.js';
 
 
 export class ErrorResponse implements flatbuffers.IUnpackableObject<ErrorResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/game-create-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { GameSummary, GameSummaryT } from './game-summary.js';
+import { GameSummary, GameSummaryT } from '../lobby/game-summary.js';
 
 
 export class GameCreateResponse implements flatbuffers.IUnpackableObject<GameCreateResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/invite-decline-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { InviteSummary, InviteSummaryT } from './invite-summary.js';
+import { InviteSummary, InviteSummaryT } from '../lobby/invite-summary.js';
 
 
 export class InviteDeclineResponse implements flatbuffers.IUnpackableObject<InviteDeclineResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/invite-redeem-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { InviteSummary, InviteSummaryT } from './invite-summary.js';
+import { InviteSummary, InviteSummaryT } from '../lobby/invite-summary.js';
 
 
 export class InviteRedeemResponse implements flatbuffers.IUnpackableObject<InviteRedeemResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/my-applications-list-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { ApplicationSummary, ApplicationSummaryT } from './application-summary.js';
+import { ApplicationSummary, ApplicationSummaryT } from '../lobby/application-summary.js';
 
 
 export class MyApplicationsListResponse implements flatbuffers.IUnpackableObject<MyApplicationsListResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/my-games-list-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { GameSummary, GameSummaryT } from './game-summary.js';
+import { GameSummary, GameSummaryT } from '../lobby/game-summary.js';
 
 
 export class MyGamesListResponse implements flatbuffers.IUnpackableObject<MyGamesListResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/my-invites-list-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { InviteSummary, InviteSummaryT } from './invite-summary.js';
+import { InviteSummary, InviteSummaryT } from '../lobby/invite-summary.js';
 
 
 export class MyInvitesListResponse implements flatbuffers.IUnpackableObject<MyInvitesListResponseT> {

ui/frontend/src/proto/galaxy/fbs/lobby/public-games-list-response.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { GameSummary, GameSummaryT } from './game-summary.js';
+import { GameSummary, GameSummaryT } from '../lobby/game-summary.js';
 
 
 export class PublicGamesListResponse implements flatbuffers.IUnpackableObject<PublicGamesListResponseT> {

ui/frontend/src/proto/galaxy/fbs/order/command-item.ts

@@ -4,30 +4,30 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { CommandFleetMerge, CommandFleetMergeT } from './command-fleet-merge.js';
-import { CommandFleetSend, CommandFleetSendT } from './command-fleet-send.js';
-import { CommandPayload, unionToCommandPayload, unionListToCommandPayload } from './command-payload.js';
-import { CommandPlanetProduce, CommandPlanetProduceT } from './command-planet-produce.js';
-import { CommandPlanetRename, CommandPlanetRenameT } from './command-planet-rename.js';
-import { CommandPlanetRouteRemove, CommandPlanetRouteRemoveT } from './command-planet-route-remove.js';
-import { CommandPlanetRouteSet, CommandPlanetRouteSetT } from './command-planet-route-set.js';
-import { CommandRaceQuit, CommandRaceQuitT } from './command-race-quit.js';
-import { CommandRaceRelation, CommandRaceRelationT } from './command-race-relation.js';
-import { CommandRaceVote, CommandRaceVoteT } from './command-race-vote.js';
-import { CommandScienceCreate, CommandScienceCreateT } from './command-science-create.js';
-import { CommandScienceRemove, CommandScienceRemoveT } from './command-science-remove.js';
-import { CommandShipClassCreate, CommandShipClassCreateT } from './command-ship-class-create.js';
-import { CommandShipClassMerge, CommandShipClassMergeT } from './command-ship-class-merge.js';
-import { CommandShipClassRemove, CommandShipClassRemoveT } from './command-ship-class-remove.js';
-import { CommandShipGroupBreak, CommandShipGroupBreakT } from './command-ship-group-break.js';
-import { CommandShipGroupDismantle, CommandShipGroupDismantleT } from './command-ship-group-dismantle.js';
-import { CommandShipGroupJoinFleet, CommandShipGroupJoinFleetT } from './command-ship-group-join-fleet.js';
-import { CommandShipGroupLoad, CommandShipGroupLoadT } from './command-ship-group-load.js';
-import { CommandShipGroupMerge, CommandShipGroupMergeT } from './command-ship-group-merge.js';
-import { CommandShipGroupSend, CommandShipGroupSendT } from './command-ship-group-send.js';
-import { CommandShipGroupTransfer, CommandShipGroupTransferT } from './command-ship-group-transfer.js';
-import { CommandShipGroupUnload, CommandShipGroupUnloadT } from './command-ship-group-unload.js';
-import { CommandShipGroupUpgrade, CommandShipGroupUpgradeT } from './command-ship-group-upgrade.js';
+import { CommandFleetMerge, CommandFleetMergeT } from '../order/command-fleet-merge.js';
+import { CommandFleetSend, CommandFleetSendT } from '../order/command-fleet-send.js';
+import { CommandPayload, unionToCommandPayload, unionListToCommandPayload } from '../order/command-payload.js';
+import { CommandPlanetProduce, CommandPlanetProduceT } from '../order/command-planet-produce.js';
+import { CommandPlanetRename, CommandPlanetRenameT } from '../order/command-planet-rename.js';
+import { CommandPlanetRouteRemove, CommandPlanetRouteRemoveT } from '../order/command-planet-route-remove.js';
+import { CommandPlanetRouteSet, CommandPlanetRouteSetT } from '../order/command-planet-route-set.js';
+import { CommandRaceQuit, CommandRaceQuitT } from '../order/command-race-quit.js';
+import { CommandRaceRelation, CommandRaceRelationT } from '../order/command-race-relation.js';
+import { CommandRaceVote, CommandRaceVoteT } from '../order/command-race-vote.js';
+import { CommandScienceCreate, CommandScienceCreateT } from '../order/command-science-create.js';
+import { CommandScienceRemove, CommandScienceRemoveT } from '../order/command-science-remove.js';
+import { CommandShipClassCreate, CommandShipClassCreateT } from '../order/command-ship-class-create.js';
+import { CommandShipClassMerge, CommandShipClassMergeT } from '../order/command-ship-class-merge.js';
+import { CommandShipClassRemove, CommandShipClassRemoveT } from '../order/command-ship-class-remove.js';
+import { CommandShipGroupBreak, CommandShipGroupBreakT } from '../order/command-ship-group-break.js';
+import { CommandShipGroupDismantle, CommandShipGroupDismantleT } from '../order/command-ship-group-dismantle.js';
+import { CommandShipGroupJoinFleet, CommandShipGroupJoinFleetT } from '../order/command-ship-group-join-fleet.js';
+import { CommandShipGroupLoad, CommandShipGroupLoadT } from '../order/command-ship-group-load.js';
+import { CommandShipGroupMerge, CommandShipGroupMergeT } from '../order/command-ship-group-merge.js';
+import { CommandShipGroupSend, CommandShipGroupSendT } from '../order/command-ship-group-send.js';
+import { CommandShipGroupTransfer, CommandShipGroupTransferT } from '../order/command-ship-group-transfer.js';
+import { CommandShipGroupUnload, CommandShipGroupUnloadT } from '../order/command-ship-group-unload.js';
+import { CommandShipGroupUpgrade, CommandShipGroupUpgradeT } from '../order/command-ship-group-upgrade.js';
 
 
 export class CommandItem implements flatbuffers.IUnpackableObject<CommandItemT> {

ui/frontend/src/proto/galaxy/fbs/order/command-payload.ts

@@ -2,29 +2,29 @@
 
 /* eslint-disable @typescript-eslint/no-unused-vars, @typescript-eslint/no-explicit-any, @typescript-eslint/no-non-null-assertion */
 
-import { CommandFleetMerge, CommandFleetMergeT } from './command-fleet-merge.js';
-import { CommandFleetSend, CommandFleetSendT } from './command-fleet-send.js';
-import { CommandPlanetProduce, CommandPlanetProduceT } from './command-planet-produce.js';
-import { CommandPlanetRename, CommandPlanetRenameT } from './command-planet-rename.js';
-import { CommandPlanetRouteRemove, CommandPlanetRouteRemoveT } from './command-planet-route-remove.js';
-import { CommandPlanetRouteSet, CommandPlanetRouteSetT } from './command-planet-route-set.js';
-import { CommandRaceQuit, CommandRaceQuitT } from './command-race-quit.js';
-import { CommandRaceRelation, CommandRaceRelationT } from './command-race-relation.js';
-import { CommandRaceVote, CommandRaceVoteT } from './command-race-vote.js';
-import { CommandScienceCreate, CommandScienceCreateT } from './command-science-create.js';
-import { CommandScienceRemove, CommandScienceRemoveT } from './command-science-remove.js';
-import { CommandShipClassCreate, CommandShipClassCreateT } from './command-ship-class-create.js';
-import { CommandShipClassMerge, CommandShipClassMergeT } from './command-ship-class-merge.js';
-import { CommandShipClassRemove, CommandShipClassRemoveT } from './command-ship-class-remove.js';
-import { CommandShipGroupBreak, CommandShipGroupBreakT } from './command-ship-group-break.js';
-import { CommandShipGroupDismantle, CommandShipGroupDismantleT } from './command-ship-group-dismantle.js';
-import { CommandShipGroupJoinFleet, CommandShipGroupJoinFleetT } from './command-ship-group-join-fleet.js';
-import { CommandShipGroupLoad, CommandShipGroupLoadT } from './command-ship-group-load.js';
-import { CommandShipGroupMerge, CommandShipGroupMergeT } from './command-ship-group-merge.js';
-import { CommandShipGroupSend, CommandShipGroupSendT } from './command-ship-group-send.js';
-import { CommandShipGroupTransfer, CommandShipGroupTransferT } from './command-ship-group-transfer.js';
-import { CommandShipGroupUnload, CommandShipGroupUnloadT } from './command-ship-group-unload.js';
-import { CommandShipGroupUpgrade, CommandShipGroupUpgradeT } from './command-ship-group-upgrade.js';
+import { CommandFleetMerge, CommandFleetMergeT } from '../order/command-fleet-merge.js';
+import { CommandFleetSend, CommandFleetSendT } from '../order/command-fleet-send.js';
+import { CommandPlanetProduce, CommandPlanetProduceT } from '../order/command-planet-produce.js';
+import { CommandPlanetRename, CommandPlanetRenameT } from '../order/command-planet-rename.js';
+import { CommandPlanetRouteRemove, CommandPlanetRouteRemoveT } from '../order/command-planet-route-remove.js';
+import { CommandPlanetRouteSet, CommandPlanetRouteSetT } from '../order/command-planet-route-set.js';
+import { CommandRaceQuit, CommandRaceQuitT } from '../order/command-race-quit.js';
+import { CommandRaceRelation, CommandRaceRelationT } from '../order/command-race-relation.js';
+import { CommandRaceVote, CommandRaceVoteT } from '../order/command-race-vote.js';
+import { CommandScienceCreate, CommandScienceCreateT } from '../order/command-science-create.js';
+import { CommandScienceRemove, CommandScienceRemoveT } from '../order/command-science-remove.js';
+import { CommandShipClassCreate, CommandShipClassCreateT } from '../order/command-ship-class-create.js';
+import { CommandShipClassMerge, CommandShipClassMergeT } from '../order/command-ship-class-merge.js';
+import { CommandShipClassRemove, CommandShipClassRemoveT } from '../order/command-ship-class-remove.js';
+import { CommandShipGroupBreak, CommandShipGroupBreakT } from '../order/command-ship-group-break.js';
+import { CommandShipGroupDismantle, CommandShipGroupDismantleT } from '../order/command-ship-group-dismantle.js';
+import { CommandShipGroupJoinFleet, CommandShipGroupJoinFleetT } from '../order/command-ship-group-join-fleet.js';
+import { CommandShipGroupLoad, CommandShipGroupLoadT } from '../order/command-ship-group-load.js';
+import { CommandShipGroupMerge, CommandShipGroupMergeT } from '../order/command-ship-group-merge.js';
+import { CommandShipGroupSend, CommandShipGroupSendT } from '../order/command-ship-group-send.js';
+import { CommandShipGroupTransfer, CommandShipGroupTransferT } from '../order/command-ship-group-transfer.js';
+import { CommandShipGroupUnload, CommandShipGroupUnloadT } from '../order/command-ship-group-unload.js';
+import { CommandShipGroupUpgrade, CommandShipGroupUpgradeT } from '../order/command-ship-group-upgrade.js';
 
 
 export enum CommandPayload {

ui/frontend/src/proto/galaxy/fbs/order/command-planet-produce.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { PlanetProduction } from './planet-production.js';
+import { PlanetProduction } from '../order/planet-production.js';
 
 
 export class CommandPlanetProduce implements flatbuffers.IUnpackableObject<CommandPlanetProduceT> {

ui/frontend/src/proto/galaxy/fbs/order/command-planet-route-remove.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { PlanetRouteLoadType } from './planet-route-load-type.js';
+import { PlanetRouteLoadType } from '../order/planet-route-load-type.js';
 
 
 export class CommandPlanetRouteRemove implements flatbuffers.IUnpackableObject<CommandPlanetRouteRemoveT> {

ui/frontend/src/proto/galaxy/fbs/order/command-planet-route-set.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { PlanetRouteLoadType } from './planet-route-load-type.js';
+import { PlanetRouteLoadType } from '../order/planet-route-load-type.js';
 
 
 export class CommandPlanetRouteSet implements flatbuffers.IUnpackableObject<CommandPlanetRouteSetT> {

ui/frontend/src/proto/galaxy/fbs/order/command-race-relation.ts

@@ -4,7 +4,7 @@
 
 import * as flatbuffers from 'flatbuffers';
 
-import { Relation } from './relation.js';
+import { Relation } from '../order/relation.js';
 
 
 export class CommandRaceRelation implements flatbuffers.IUnpackableObject<CommandRaceRelationT> {