Addresses reviewer feedback on #13377:
1. Restore all stripped docstrings (_load_config, _is_breaker_open,
sync_turn, register, _get_client, _read_filters, _write_filters,
_unwrap_results, save_config) and section dividers
2. Revert api_key to required:true in schema — self-hosted Mem0 also
requires auth by default; validation in _get_client() handles the
either/or logic separately from the schema
3. Confirm secret:true remains on api_key (already correct)
452a725ae1