Stage 10: admin console & dictionary ops (complaint review, hot-reload, broadcasts)

Server-rendered admin console in the backend at /_gm (internal/adminconsole),
fronted on the gateway's public listener by Basic-Auth + a verbatim reverse proxy
(mounted on the edge mux below the h2c wrap). A same-origin check guards its POSTs;
no operator identity is tracked. This supersedes the Stage 6 gateway-fronts-
/api/v1/admin model: GATEWAY_ADMIN_ADDR and the backend /api/v1/admin ping are
dropped and gateway/internal/admin is repurposed to the verbatim proxy.

- Complaints: migration 00008 (+ jetgen) adds disposition/resolution_note/
  resolved_at/applied_in_version + the deferred status CHECK; resolution feeds a
  query-derived pending dictionary-change pipeline (marked applied after a reload).
- Dictionary hot-reload: per-version subdir BACKEND_DICT_DIR/<version>/ via the new
  Registry.LoadAvailable; engine.OpenWithVersions restores resident versions on
  restart. Partially addresses TODO-2.
- Broadcasts: a backend Telegram-connector client (internal/connector,
  BACKEND_CONNECTOR_ADDR) for SendToUser / SendToGameChannel (discharges the Stage 9
  forward-note).
- Admin reads: account.ListAccounts/CountAccounts/Identities and
  game.ListGames/CountGames/GameByID/ListComplaints/GetComplaint/CountComplaints/
  ResolveComplaint/DictionaryChanges/MarkChangesApplied.
- Tests: adminconsole render, engine reload, same-origin guard, gateway verbatim
  proxy + h2c console mount, inttest complaint pipeline + list/count + /_gm console.
- Docs: PLAN (Stage 10 done + refinements + TODO-2), ARCHITECTURE §1/§5/§6/§12/§13,
  FUNCTIONAL (+_ru), TESTING, backend/gateway READMEs.

backend/internal/adminconsole/views.go

@@ -0,0 +1,200 @@
+package adminconsole
+
+// The *View types are the display models the gin handlers fill and the templates
+// render. Time values are pre-formatted to strings by the handlers so the
+// templates stay logic-free.
+
+// Pager is the shared list pagination state.
+type Pager struct {
+	Page     int
+	PageSize int
+	Total    int
+	HasPrev  bool
+	HasNext  bool
+	PrevPage int
+	NextPage int
+}
+
+// NewPager builds the pagination state for a 1-based page of pageSize over total
+// items.
+func NewPager(page, pageSize, total int) Pager {
+	if page < 1 {
+		page = 1
+	}
+	p := Pager{Page: page, PageSize: pageSize, Total: total, PrevPage: page - 1, NextPage: page + 1}
+	p.HasPrev = page > 1
+	p.HasNext = page*pageSize < total
+	return p
+}
+
+// VariantVersions lists the dictionary versions resident for one variant.
+type VariantVersions struct {
+	Variant  string
+	Latest   string
+	Versions []string
+}
+
+// DashboardView is the landing-page summary.
+type DashboardView struct {
+	Accounts       int
+	Games          int
+	ActiveGames    int
+	OpenComplaints int
+	PendingChanges int
+	Variants       []VariantVersions
+}
+
+// UsersView is the paginated account list.
+type UsersView struct {
+	Items []UserRow
+	Pager Pager
+}
+
+// UserRow is one account row in the list.
+type UserRow struct {
+	ID          string
+	DisplayName string
+	Kind        string
+	Language    string
+	Guest       bool
+	CreatedAt   string
+}
+
+// UserDetailView is one account with its stats, identities and recent games.
+type UserDetailView struct {
+	ID                     string
+	DisplayName            string
+	Language               string
+	TimeZone               string
+	Guest                  bool
+	NotificationsInAppOnly bool
+	HintBalance            int
+	CreatedAt              string
+	HasStats               bool
+	Stats                  StatsRow
+	Identities             []IdentityRow
+	Games                  []GameRow
+	TelegramID             string
+	ConnectorEnabled       bool
+}
+
+// StatsRow is an account's lifetime statistics.
+type StatsRow struct {
+	Wins          int
+	Losses        int
+	Draws         int
+	MaxGamePoints int
+	MaxWordPoints int
+}
+
+// IdentityRow is one platform/email identity of an account.
+type IdentityRow struct {
+	Kind       string
+	ExternalID string
+	Confirmed  bool
+	CreatedAt  string
+}
+
+// GameRow is one game row in a list.
+type GameRow struct {
+	ID        string
+	Variant   string
+	Status    string
+	Players   int
+	UpdatedAt string
+}
+
+// GamesView is the paginated games list, optionally filtered by status.
+type GamesView struct {
+	Items  []GameRow
+	Status string
+	Pager  Pager
+}
+
+// GameDetailView is one game with its seats.
+type GameDetailView struct {
+	ID          string
+	Variant     string
+	DictVersion string
+	Status      string
+	Players     int
+	ToMove      int
+	EndReason   string
+	MoveCount   int
+	CreatedAt   string
+	UpdatedAt   string
+	FinishedAt  string
+	Seats       []SeatRow
+}
+
+// SeatRow is one seat of a game.
+type SeatRow struct {
+	Seat        int
+	DisplayName string
+	AccountID   string
+	Score       int
+	HintsUsed   int
+	Winner      bool
+}
+
+// ComplaintsView is the paginated complaint review queue.
+type ComplaintsView struct {
+	Items  []ComplaintRow
+	Status string
+	Pager  Pager
+}
+
+// ComplaintRow is one complaint row in the queue.
+type ComplaintRow struct {
+	ID          string
+	Word        string
+	Variant     string
+	WasValid    bool
+	Status      string
+	Disposition string
+	CreatedAt   string
+}
+
+// ComplaintDetailView is one complaint with its resolution state and form.
+type ComplaintDetailView struct {
+	ID             string
+	Word           string
+	Variant        string
+	DictVersion    string
+	WasValid       bool
+	Note           string
+	Status         string
+	Disposition    string
+	ResolutionNote string
+	CreatedAt      string
+	ResolvedAt     string
+	GameID         string
+	Resolved       bool
+}
+
+// DictionaryView lists the resident versions per variant and the pending
+// wordlist changes from accepted complaints.
+type DictionaryView struct {
+	Variants []VariantVersions
+	Changes  []DictChangeRow
+}
+
+// DictChangeRow is one pending wordlist edit.
+type DictChangeRow struct {
+	Variant    string
+	Word       string
+	Action     string
+	ResolvedAt string
+}
+
+// BroadcastView is the operator-broadcast form page.
+type BroadcastView struct {
+	ConnectorEnabled bool
+}
+
+// MessageView is the result page shown after a POST action.
+type MessageView struct {
+	Heading string
+	Body    string
+	Back    string
+}