perf(battlesnake): defer ordered lifecycle bookkeeping

- Acknowledge start and end without waiting for persistence or dashboards.
- Keep runtime creation and finished-game removal on the response path.
- Serialize start, turn, and end bookkeeping per game in Quart tasks.
- Capture turn thinking before scheduling deferred persistence.
- Defer start metrics, logging, and stale-game pruning.
- Run legacy history exports in a worker thread.
- Record results and end metrics even when history export fails.
- Drain pending bookkeeping before closing storage during shutdown.
- Test sub-500 ms responses with slow backends and real SQLite.
- Cover event ordering, export failures, and rejected user agents.

server/blueprints/battlesnake.py

@@ -5,7 +5,6 @@ from quart import Blueprint, request, jsonify
 
 from quart_common.web.decorators import require_user_agent
 from quart_common.web.logger import await_log
-from server.database import StorageLoader
 from snakes import DEFAULT_SNAKE_CONFIG
 from server.GameBoard import GameBoard
 from server.Files import read_file
@@ -47,14 +46,13 @@ def create_battlesnake_blueprint(server:'Server') -> Blueprint:
   @require_user_agent(("BattlesnakeEngine", "BattlesnakeArena"), abort_code=404)
   async def on_start():
     server.metrics_collector.record_http_request('start')
-    await server.game_runtime.prune_stale_games()
     game_state = await request.get_json()
-    game_board = await server.game_runtime.create_game_board(game_state)
-    await server.gameplay_tracking.record_gameplay_start(game_state, game_board)
-    await server.dashboard_query.push_dashboard_games_update(
-      game_state, trigger='game_started',
+    game_board = await server.game_runtime.create_game_board(game_state, publish_metrics=False)
+    active_count = len(server.game_runtime.running_games)
+    server.game_lifecycle.submit(
+      game_state['game']['id'],
+      lambda: server.game_lifecycle.started(game_state, game_board, active_count),
     )
-    await await_log(server.logger.info(f'GAME START: {game_state['game']}'))
     return 'ok'
 
   @blueprint.post('/move')
@@ -79,8 +77,10 @@ def create_battlesnake_blueprint(server:'Server') -> Blueprint:
     except TimeoutError:
       await await_log(server.logger.warning(f'MOVE TIMEOUT: turn={game_state.get("turn")}, game={game_id}, returning fallback {next_move!r}'))
 
-    await server.gameplay_tracking.record_gameplay_turn(game_state, next_move, game_board)
-    await server.dashboard_query.push_dashboard_game_replay_update(game_id)
+    thinking = server.gameplay_tracking._extract_latest_snake_thinking(game_board)
+    server.game_lifecycle.submit(
+      game_id, lambda: server.game_lifecycle.turn(game_state, next_move, thinking),
+    )
     elapsed_ms = (time.perf_counter() - move_started) * 1000.0
     await server.metrics_collector.record_move(next_move, elapsed_ms)
 
@@ -93,29 +93,16 @@ def create_battlesnake_blueprint(server:'Server') -> Blueprint:
   @require_user_agent(("BattlesnakeEngine", "BattlesnakeArena"), abort_code=404)
   async def on_end():
     server.metrics_collector.record_http_request('end')
-    await server.game_runtime.prune_stale_games()
     game_state = await request.get_json()
-    if server.store_game_state:
-      game_board = cast(GameBoard, await server.game_runtime.get_game_board(game_state, end=True))
-      if server.check_tls_security:
-        await game_board.save(
-          StorageLoader.build(server.storage_type),
-          file_path=os.path.join(server.data_path, 'data'),
-          database=os.getenv('EDGEDB_DATABASE', None),
-          tls_security=None,
-        )
-      else:
-        await game_board.save(
-          StorageLoader.build(server.storage_type),
-          file_path=os.path.join(server.data_path, 'data'),
-          database=os.getenv('EDGEDB_DATABASE', None),
-        )
-
-    await server.gameplay_tracking.record_gameplay_end(game_state)
-    await server.dashboard_query.push_dashboard_games_update(game_state)
-    await await_log(server.logger.info(f'GAME ENDED: Winner is {[x['name'] for x in game_state['board']['snakes']]}'))
+    game_id = game_state['game']['id']
+    game_board = server.game_runtime.running_games.get(game_id)
+    if game_board is not None:
+      game_board.read_game_data(game_state)
+      game_board.end_game(game_state)
     await server.game_runtime.delete_game_board(game_state)
-    await server.metrics_collector.record_game_end(game_state)
+    server.game_lifecycle.submit(
+      game_id, lambda: server.game_lifecycle.ended(game_state, game_board),
+    )
     return 'ok'
 
   # @blueprint.get('/cleanup')