Move Fail2Ban exceptions into central app.exceptions module

backend/tests/test_services/test_fail2ban_metadata_service.py

@@ -5,7 +5,7 @@ from __future__ import annotations
 from unittest.mock import AsyncMock, patch
 
 from app.services.fail2ban_metadata_service import Fail2BanMetadataService
-from app.utils.fail2ban_client import Fail2BanConnectionError
+from app.exceptions import Fail2BanConnectionError
 
 
 async def test_get_db_path_caches_result() -> None: