Move config file exceptions into app.exceptions

Move ConfigDirError, ConfigFileNotFoundError, ConfigFileExistsError, ConfigFileWriteError, and ConfigFileNameError from raw_config_io_service into the shared domain exception module. Update router and tests to import the exceptions from app.exceptions.

backend/tests/test_services/test_file_config_service.py

@@ -8,12 +8,14 @@ import pytest
 
 from app.models.config import ActionConfigUpdate, FilterConfigUpdate, JailFileConfigUpdate
 from app.models.file_config import ConfFileCreateRequest, ConfFileUpdateRequest
-from app.services.raw_config_io_service import (
+from app.exceptions import (
     ConfigDirError,
     ConfigFileExistsError,
     ConfigFileNameError,
     ConfigFileNotFoundError,
     ConfigFileWriteError,
+)
+from app.services.raw_config_io_service import (
     _parse_enabled,
     _set_enabled_in_content,
     _validate_new_name,