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

ui/buf.gen.yaml

@@ -0,0 +1,9 @@
+# Generates the TypeScript Connect client for the edge envelope service from the
+# same gateway/proto/edge/v1/edge.proto the Go gateway uses. The committed output
+# lives under src/gen/edge/; CI only builds it (dev-time codegen, like pkg/Makefile).
+version: v2
+plugins:
+  - local: ./node_modules/.bin/protoc-gen-es
+    out: src/gen
+    opt:
+      - target=ts