Configure my existing standalone Codex CLI to use MandAPI. Read the installed client's current configuration format and preserve my existing project, approval and sandbox settings. Back up the config before merging a custom provider named mandapi with base_url=https://api.mandapi.com/v1, wire_api=responses and env_key=MANDAPI_API_KEY. Keep the actual key outside config.toml and never display it. Use the exact account-visible model ID I provide; ask for it if missing. Do not infer a model's context limit, tool support or Responses features from its name. Check that the intended process can see the environment variable and, when credentials are available, run one short read-only README summary. Report the files changed, result and restoration steps. Do not alter MandAPI Connect's private configuration or purchase credits.