feat: add live replays and PostgreSQL maintenance tools

- Stream compact live replay updates across local and clustered dashboards.
- Render responsive snake bodies as SVG paths with aligned custom icons.
- Add cache-busted assets, replay fallback routes, and live-follow playback.
- Support PostgreSQL benchmark sampling and idempotent SQLite migration.
- Add dry-run cleanup for old low-quality PostgreSQL replay payloads.
- Reward safe perimeter lanes and bump Prism to version 1.5.0.
- Add backend, migration, dashboard, and perimeter regression coverage.

server/services/dashboard_query.py

@@ -12,12 +12,22 @@ class DashboardQueryService:
     self.ws_hub = ws_hub
     self.logger = logger
     self.dashboard_running_game_stale_sec = dashboard_running_game_stale_sec
-    self.publish_notice:Callable[[str], Awaitable[None]] | None = None
+    self.publish_notice:Callable[[str, str|None], Awaitable[None]] | None = None
 
-  def set_publish_notice(self, publish_notice:Callable[[str], Awaitable[None]]) -> None:
+  def set_publish_notice(
+    self, publish_notice:Callable[[str, str|None], Awaitable[None]],
+  ) -> None:
     self.publish_notice = publish_notice
 
-  async def on_dashboard_games_update_notice(self, trigger:str) -> None:
+  async def on_dashboard_games_update_notice(
+    self, trigger:str, game_id:str|None=None,
+  ) -> None:
+    if trigger == 'game_turn' and game_id:
+      await self.push_dashboard_game_replay_update(
+        game_id,
+        publish_cluster=False,
+      )
+      return
     await self.push_dashboard_games_update(
       game_state=None,
       publish_cluster=False,
@@ -56,6 +66,22 @@ class DashboardQueryService:
       'replay': replay_payload,
     }
 
+  async def build_dashboard_game_replay_update_event(self, game_id:str) -> dict:
+    replay_payload = await self.get_dashboard_game_replay(game_id)
+    if replay_payload is None:
+      return {
+        'type': 'dashboard_game_replay_update',
+        'game_id': game_id,
+        'error': 'game_not_found',
+      }
+    turns = replay_payload.get('turns', [])
+    return {
+      'type': 'dashboard_game_replay_update',
+      'game_id': game_id,
+      'game': replay_payload.get('game', {}),
+      'turn': turns[-1] if turns else None,
+    }
+
   async def handle_dashboard_ws_request(self, payload_raw:object) -> dict|None:
     if not isinstance(payload_raw, str):
       return None
@@ -95,7 +121,24 @@ class DashboardQueryService:
     )
     await self.ws_hub.broadcast_payload(event_payload)
     if publish_cluster and self.publish_notice is not None:
-      await self.publish_notice(str(event_payload.get('trigger') or ''))
+      game_id = None
+      if game_state is not None:
+        game_id = game_state.get('game', {}).get('id')
+      await self.publish_notice(
+        str(event_payload.get('trigger') or ''), game_id,
+      )
+
+  async def push_dashboard_game_replay_update(
+    self, game_id:str, publish_cluster:bool=True,
+  ) -> None:
+    if self.gameplay_database is None:
+      return
+    event_payload = await self.build_dashboard_game_replay_update_event(game_id)
+    if event_payload.get('error'):
+      return
+    await self.ws_hub.broadcast_payload(event_payload)
+    if publish_cluster and self.publish_notice is not None:
+      await self.publish_notice('game_turn', game_id)
 
   async def get_dashboard_summary(self) -> dict:
     if self.gameplay_database is None: