BatchCreateImportedApiKeysErrorCode classifies per-item batch import failures. - BATCH_CREATE_IMPORTED_API_KEYS_ERROR_UNSPECIFIED: No error (import succeeded) - BATCH_CREATE_IMPORTED_API_KEYS_ERROR_INVALID_ARGUMENT: The key data is malformed or missing required fields - BATCH_CREATE_IMPORTED_API_KEYS_ERROR_ALREADY_EXISTS: A key with this identifier already exists - BATCH_CREATE_IMPORTED_API_KEYS_ERROR_FAILED_PRECONDITION: State conflict prevents the import - BATCH_CREATE_IMPORTED_API_KEYS_ERROR_INTERNAL: Server error during import - BATCH_CREATE_IMPORTED_API_KEYS_ERROR_RESOURCE_EXHAUSTED: Per-tenant quota cap reached