refactor: break up lifespan() into focused helpers

Extract _init_services(), _auto_prune(), _register_error_recorder(),
and _shutdown() from the 142-line lifespan() context manager, reducing
it to ~25 lines that read as a clear startup/shutdown sequence.

Fixes #514

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/dashboard/app.py

@@ -329,33 +329,21 @@ async def _discord_token_watcher() -> None:
                 logger.warning("Discord auto-start failed: %s", exc)
 
 
-@asynccontextmanager
-async def lifespan(app: FastAPI):
-    """Application lifespan manager with non-blocking startup."""
-
-    # Validate security config (no-op in test mode)
+def _init_services() -> None:
+    """Validate config, enable event persistence, and init Spark engine."""
     from config import validate_startup
+    from infrastructure.events.bus import init_event_bus_persistence
+    from spark.engine import get_spark_engine
 
     validate_startup()
-
-    # Enable event persistence (unified EventBus + swarm event_log)
-    from infrastructure.events.bus import init_event_bus_persistence
-
     init_event_bus_persistence()
 
-    # Create all background tasks without waiting for them
-    briefing_task = asyncio.create_task(_briefing_scheduler())
-    thinking_task = asyncio.create_task(_thinking_scheduler())
-    loop_qa_task = asyncio.create_task(_loop_qa_scheduler())
-    presence_task = asyncio.create_task(_presence_watcher())
-
-    # Initialize Spark Intelligence engine
-    from spark.engine import get_spark_engine
-
     if get_spark_engine().enabled:
         logger.info("Spark Intelligence active — event capture enabled")
 
-    # Auto-prune old vector store memories on startup
+
+def _auto_prune() -> None:
+    """Run startup housekeeping: prune memories, thoughts, events, and check vault size."""
     if settings.memory_prune_days > 0:
         try:
             from timmy.memory_system import prune_memories
@@ -373,7 +361,6 @@ async def lifespan(app: FastAPI):
         except Exception as exc:
             logger.debug("Memory auto-prune skipped: %s", exc)
 
-    # Auto-prune old thoughts on startup
     if settings.thoughts_prune_days > 0:
         try:
             from timmy.thinking import thinking_engine
@@ -391,7 +378,6 @@ async def lifespan(app: FastAPI):
         except Exception as exc:
             logger.debug("Thought auto-prune skipped: %s", exc)
 
-    # Auto-prune old system events on startup
     if settings.events_prune_days > 0:
         try:
             from swarm.event_log import prune_old_events
@@ -409,7 +395,6 @@ async def lifespan(app: FastAPI):
         except Exception as exc:
             logger.debug("Event auto-prune skipped: %s", exc)
 
-    # Warn if memory vault exceeds size limit
     if settings.memory_vault_max_mb > 0:
         try:
             vault_path = Path(settings.repo_root) / "memory" / "notes"
@@ -425,17 +410,9 @@ async def lifespan(app: FastAPI):
         except Exception as exc:
             logger.debug("Vault size check skipped: %s", exc)
 
-    # Start Workshop presence heartbeat with WS relay
-    from dashboard.routes.world import broadcast_world_state
-    from timmy.workshop_state import WorkshopHeartbeat
 
-    workshop_heartbeat = WorkshopHeartbeat(on_change=broadcast_world_state)
-    await workshop_heartbeat.start()
-
-    # Start chat integrations in background
-    chat_task = asyncio.create_task(_start_chat_integrations_background())
-
-    # Register session logger with error capture (breaks infrastructure → timmy circular dep)
+def _register_error_recorder() -> None:
+    """Wire the session logger into the error-capture system."""
     try:
         from infrastructure.error_capture import register_error_recorder
         from timmy.session_logger import get_session_logger
@@ -444,18 +421,18 @@ async def lifespan(app: FastAPI):
     except Exception:
         logger.debug("Failed to register error recorder")
 
-    logger.info("✓ Dashboard ready for requests")
 
-    yield
-
-    # Cleanup on shutdown
+async def _shutdown(
+    tasks: list[asyncio.Task],
+    workshop_heartbeat: object,
+) -> None:
+    """Stop integrations, close sessions, and cancel background tasks."""
     from integrations.chat_bridge.vendors.discord import discord_bot
     from integrations.telegram_bot.bot import telegram_bot
 
     await discord_bot.stop()
     await telegram_bot.stop()
 
-    # Close MCP tool server sessions
     try:
         from timmy.mcp_tools import close_mcp_sessions
 
@@ -463,15 +440,46 @@ async def lifespan(app: FastAPI):
     except Exception as exc:
         logger.debug("MCP shutdown: %s", exc)
 
-    await workshop_heartbeat.stop()
+    await workshop_heartbeat.stop()  # type: ignore[union-attr]
 
-    for task in [briefing_task, thinking_task, chat_task, loop_qa_task, presence_task]:
-        if task:
-            task.cancel()
-            try:
-                await task
-            except asyncio.CancelledError:
-                pass
+    for task in tasks:
+        task.cancel()
+        try:
+            await task
+        except asyncio.CancelledError:
+            pass
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    """Application lifespan manager with non-blocking startup."""
+    _init_services()
+    _auto_prune()
+
+    # Create all background tasks without waiting for them
+    bg_tasks = [
+        asyncio.create_task(_briefing_scheduler()),
+        asyncio.create_task(_thinking_scheduler()),
+        asyncio.create_task(_loop_qa_scheduler()),
+        asyncio.create_task(_presence_watcher()),
+    ]
+
+    # Start Workshop presence heartbeat with WS relay
+    from dashboard.routes.world import broadcast_world_state
+    from timmy.workshop_state import WorkshopHeartbeat
+
+    workshop_heartbeat = WorkshopHeartbeat(on_change=broadcast_world_state)
+    await workshop_heartbeat.start()
+
+    # Start chat integrations in background
+    bg_tasks.append(asyncio.create_task(_start_chat_integrations_background()))
+
+    _register_error_recorder()
+    logger.info("✓ Dashboard ready for requests")
+
+    yield
+
+    await _shutdown(bg_tasks, workshop_heartbeat)
 
 
 app = FastAPI(