ui/phase-25: backend turn-cutoff guard + auto-pause + UI sync protocol

Backend now owns the turn-cutoff and pause guards the order tab
relies on: the scheduler flips runtime_status between
generation_in_progress and running around every engine tick, a
failed tick auto-pauses the game through OnRuntimeSnapshot, and a
new game.paused notification kind fans out alongside
game.turn.ready. The user-games handlers reject submits with
HTTP 409 turn_already_closed or game_paused depending on the
runtime state.

UI delegates auto-sync to a new OrderQueue: offline detection,
single retry on reconnect, conflict / paused classification.
OrderDraftStore surfaces conflictBanner / pausedBanner runes,
clears them on local mutation or on a game.turn.ready push via
resetForNewTurn. The order tab renders the matching banners and
the new conflict per-row badge; i18n bundles cover en + ru.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

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`.