fix issues

services/demo_session/app/services/session_manager.py

@@ -15,6 +15,7 @@ from app.models import DemoSession, DemoSessionStatus, CloningStatus
 from app.core.redis_wrapper import DemoRedisWrapper
 from app.core import settings
 from app.services.clone_orchestrator import CloneOrchestrator
+from app.services.cleanup_service import DemoCleanupService
 from app.repositories.demo_session_repository import DemoSessionRepository
 
 logger = structlog.get_logger()