User feedback: persist non-secret model endpoint settings

[qqqys]

This was generated by AI during triage.

User feedback

The CLI currently requires model name, compatible API endpoint, and credential source to be exported again in each shell. I want a durable user-level settings file for non-secret model configuration, while the API key itself remains in a named environment variable and is never stored in plaintext.

Expected behavior

• Read model name, compatible base URL, and API-key environment-variable name from a user-owned settings file.
• Keep environment variables as deterministic overrides.
• Reuse the existing explicit settings path across interactive, headless, preflight, resume, and health flows.
• Never discover repository-local settings automatically.
• Reject plaintext apiKey fields and redact credentials, sensitive URL parts, and host-specific paths in diagnostics and terminal evidence.

Validation context

This request follows direct server dogfooding of the current release: the CLI launches successfully, but settings cannot yet persist model endpoint selection for actual model-backed use. The linked execution issue contains the detailed acceptance and test contract.

[qwen-code-dev-bot]

Thanks for the feedback. This request has been normalized into the bot-authored execution issue #75 (Configuration: load model endpoint and selection from user settings), which carries the detailed acceptance, test, and dogfood contract. Implementation, review, and merge tracking happen there.

This original report stays open until #75 merges and targeted post-merge dogfood succeeds, at which point it will be closed with the pull request, commits, and verification evidence.