Using Codex Subscription tokens

[dee-men]

Current implementation requires an API key. Codex subscription allows use of custom harness. Supporting this could be beneficial to the community to experiment.

I am happy to add this feature if there is interest.

Thanks!

[codelion]

Yes, I'd take a PR for this. Please use Codex app-server rather than reading the CLI token files directly; it now has managed ChatGPT browser/device-code login and refreshes the tokens itself:

https://learn.chatgpt.com/docs/app-server#auth-endpoints

Keep the current API-key path working and make this opt-in. A mocked test around the auth boundary plus docs would be enough for a first pass.