Stage 7 (wip): wire remaining ops (backend REST, FBS, gateway transcode) + real UI transport

backend: REST handlers for pass/exchange/resign/hint/evaluate/check_word/complaint/history/chat-list/nudge + new game.ListForAccount (my games) + seat display_name resolution
pkg/fbs: GameActionRequest/ExchangeRequest/EvalRequest/EvalResult/CheckWordRequest/WordCheckResult/ComplaintRequest/HintResult/History/GameList/ChatList + SeatView.display_name; committed Go regenerated (flatc 23.5.26)
gateway: 11 new transcode ops + backendclient methods + FB encoders
ui: edge TS codegen (flatc --ts + protoc-gen-es, committed), FlatBuffers<->model codec, real connect-web transport (binary, bearer auth, Subscribe). prod bundle ~69KB gzip JS

gateway/internal/backendclient/api.go

@@ -54,11 +54,12 @@ type MoveRecordResp struct {
 
 // SeatResp is one seat's public standing.
 type SeatResp struct {
-	Seat      int    `json:"seat"`
-	AccountID string `json:"account_id"`
-	Score     int    `json:"score"`
-	HintsUsed int    `json:"hints_used"`
-	IsWinner  bool   `json:"is_winner"`
+	Seat        int    `json:"seat"`
+	AccountID   string `json:"account_id"`
+	DisplayName string `json:"display_name"`
+	Score       int    `json:"score"`
+	HintsUsed   int    `json:"hints_used"`
+	IsWinner    bool   `json:"is_winner"`
 }
 
 // GameResp is the shared game summary.
@@ -189,3 +190,120 @@ func (c *Client) ChatPost(ctx context.Context, userID, gameID, body, clientIP st
 		map[string]string{"body": body}, &out)
 	return out, err
 }
+
+// HintResultResp is the top-ranked move plus the remaining hint budget.
+type HintResultResp struct {
+	Move           MoveRecordResp `json:"move"`
+	HintsRemaining int            `json:"hints_remaining"`
+}
+
+// EvalResultResp is an unlimited move preview.
+type EvalResultResp struct {
+	Legal bool     `json:"legal"`
+	Score int      `json:"score"`
+	Words []string `json:"words"`
+}
+
+// WordCheckResp is a dictionary lookup outcome.
+type WordCheckResp struct {
+	Word  string `json:"word"`
+	Legal bool   `json:"legal"`
+}
+
+// HistoryResp is a game's decoded move journal.
+type HistoryResp struct {
+	GameID string           `json:"game_id"`
+	Moves  []MoveRecordResp `json:"moves"`
+}
+
+// GameListResp is the caller's games for the lobby.
+type GameListResp struct {
+	Games []GameResp `json:"games"`
+}
+
+// ChatListResp is a game's chat history.
+type ChatListResp struct {
+	Messages []ChatResp `json:"messages"`
+}
+
+func (c *Client) gamePath(gameID, suffix string) string {
+	return "/api/v1/user/games/" + url.PathEscape(gameID) + suffix
+}
+
+// Pass forfeits the player's turn.
+func (c *Client) Pass(ctx context.Context, userID, gameID string) (MoveResultResp, error) {
+	var out MoveResultResp
+	err := c.do(ctx, http.MethodPost, c.gamePath(gameID, "/pass"), userID, "", struct{}{}, &out)
+	return out, err
+}
+
+// Exchange swaps the chosen rack tiles back into the bag.
+func (c *Client) Exchange(ctx context.Context, userID, gameID string, tiles []string) (MoveResultResp, error) {
+	var out MoveResultResp
+	err := c.do(ctx, http.MethodPost, c.gamePath(gameID, "/exchange"), userID, "",
+		map[string]any{"tiles": tiles}, &out)
+	return out, err
+}
+
+// Resign resigns the player from the game.
+func (c *Client) Resign(ctx context.Context, userID, gameID string) (MoveResultResp, error) {
+	var out MoveResultResp
+	err := c.do(ctx, http.MethodPost, c.gamePath(gameID, "/resign"), userID, "", struct{}{}, &out)
+	return out, err
+}
+
+// Hint reveals the top-ranked move and spends a hint.
+func (c *Client) Hint(ctx context.Context, userID, gameID string) (HintResultResp, error) {
+	var out HintResultResp
+	err := c.do(ctx, http.MethodPost, c.gamePath(gameID, "/hint"), userID, "", struct{}{}, &out)
+	return out, err
+}
+
+// Evaluate previews a tentative play's legality and score.
+func (c *Client) Evaluate(ctx context.Context, userID, gameID, dir string, tiles []TileJSON) (EvalResultResp, error) {
+	var out EvalResultResp
+	err := c.do(ctx, http.MethodPost, c.gamePath(gameID, "/evaluate"), userID, "",
+		map[string]any{"dir": dir, "tiles": tiles}, &out)
+	return out, err
+}
+
+// CheckWord looks a word up in the game's pinned dictionary.
+func (c *Client) CheckWord(ctx context.Context, userID, gameID, word string) (WordCheckResp, error) {
+	var out WordCheckResp
+	err := c.do(ctx, http.MethodGet, c.gamePath(gameID, "/check_word")+"?word="+url.QueryEscape(word), userID, "", nil, &out)
+	return out, err
+}
+
+// Complaint disputes a word-check result.
+func (c *Client) Complaint(ctx context.Context, userID, gameID, word, note string) error {
+	return c.do(ctx, http.MethodPost, c.gamePath(gameID, "/complaint"), userID, "",
+		map[string]string{"word": word, "note": note}, nil)
+}
+
+// History returns a game's decoded move journal.
+func (c *Client) History(ctx context.Context, userID, gameID string) (HistoryResp, error) {
+	var out HistoryResp
+	err := c.do(ctx, http.MethodGet, c.gamePath(gameID, "/history"), userID, "", nil, &out)
+	return out, err
+}
+
+// ChatList returns a game's chat history.
+func (c *Client) ChatList(ctx context.Context, userID, gameID string) (ChatListResp, error) {
+	var out ChatListResp
+	err := c.do(ctx, http.MethodGet, c.gamePath(gameID, "/chat"), userID, "", nil, &out)
+	return out, err
+}
+
+// Nudge posts a nudge to the player whose turn is awaited.
+func (c *Client) Nudge(ctx context.Context, userID, gameID string) (ChatResp, error) {
+	var out ChatResp
+	err := c.do(ctx, http.MethodPost, c.gamePath(gameID, "/nudge"), userID, "", struct{}{}, &out)
+	return out, err
+}
+
+// GamesList returns the caller's active and finished games.
+func (c *Client) GamesList(ctx context.Context, userID string) (GameListResp, error) {
+	var out GameListResp
+	err := c.do(ctx, http.MethodGet, "/api/v1/user/games", userID, "", nil, &out)
+	return out, err
+}