Add dispute system

backend/app/main.py

@@ -9,6 +9,7 @@ from app.core.config import settings
 from app.core.database import engine, Base, async_session_maker
 from app.api.v1 import router as api_router
 from app.services.event_scheduler import event_scheduler
+from app.services.dispute_scheduler import dispute_scheduler
 
 
 @asynccontextmanager
@@ -23,13 +24,15 @@ async def lifespan(app: FastAPI):
     (upload_dir / "covers").mkdir(parents=True, exist_ok=True)
     (upload_dir / "proofs").mkdir(parents=True, exist_ok=True)
 
-    # Start event scheduler
+    # Start schedulers
     await event_scheduler.start(async_session_maker)
+    await dispute_scheduler.start(async_session_maker)
 
     yield
 
     # Shutdown
     await event_scheduler.stop()
+    await dispute_scheduler.stop()
     await engine.dispose()