Add a feature that automatically waits for a model provider's rate limit to e...

Add a feature that automatically waits for a model provider's rate limit to expire and retries the request instead of immediately failing.

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| Field | Value |
| --- | --- |
| App version | 1.0.25 |
| OS | Windows 10.0.26200 |
| Theme | ABOLKOG |
| Path | /chat |
| Tenure | Week 2 |

Start by tracing the /chat request path and locating where model-provider rate-limit failures are handled. Determine how the provider communicates the retry delay and how retries should affect the user-visible request flow; done means rate-limited requests wait and retry instead of immediately failing, with existing failure behavior preserved otherwise.

Written by the indexing model from the issue text.