Changing the API key in the settings UI does not immediately update the API key in an existing chat

I was having an issue where my api key was getting quota exceeded errors. only after using `/providers set openai apiKey` did the apiKey get updated for the existing chat

<img width="793" height="590" alt="Image" src="https://github.com/user-attachments/assets/2eff9f7a-c24d-490b-8552-2cf0ba5909bb" />