feat(memory): add automated nightly consolidation at 4:00 AM UTC

Step 2 of memory system overhaul: automated scheduling.

- New consolidation_scheduler.py: run_nightly_consolidation() function that
  checks Cat health, triggers consolidation via WebSocket, and tracks
  run history with success/failure stats
- bot.py on_ready: register APScheduler cron job (hour=4, minute=0)
  alongside the existing daily DM analysis job
- routes/memory.py: expose consolidation status (last_run, last_result,
  last_error, is_running, total_runs, successful_runs) in the
  /memory/status API response
- Web UI: show consolidation schedule info (last run time, success/fail,
  run counts) below the manual consolidate button, with 'running now'
  indicator when active

The 'sleep consolidation' metaphor is now actually automated instead of
being manual-only.

bot/routes/memory.py

@@ -14,15 +14,17 @@ router = APIRouter()
 
 @router.get("/memory/status")
 async def get_cat_memory_status():
-    """Get Cheshire Cat connection status and feature flag."""
+    """Get Cheshire Cat connection status, feature flag, and consolidation state."""
     from utils.cat_client import cat_adapter
+    from utils.consolidation_scheduler import get_consolidation_status
     is_healthy = await cat_adapter.health_check()
     return {
         "enabled": globals.USE_CHESHIRE_CAT,
         "healthy": is_healthy,
         "url": globals.CHESHIRE_CAT_URL,
         "circuit_breaker_active": cat_adapter._is_circuit_broken(),
-        "consecutive_failures": cat_adapter._consecutive_failures
+        "consecutive_failures": cat_adapter._consecutive_failures,
+        "consolidation": get_consolidation_status(),
     }