Cleanup and update mistral models based on their documentation (#55443)

Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [ ] Unsafe blocks (if any) have justifying comments
- [ ] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [x] Tests cover the new/changed behavior
- [ ] Performance impact has been considered and is acceptable

Release Notes:

- Mistral: Added Ministral 3 models and removed deprecated models

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Signed-off-by: Gabriel Linder <linder.gabriel@gmail.com>
0dd5427e02Gabriel Linder committed on 5/6/2026, 12:27:58 PM· committed by GitHubparent86e64e2
2 files changedLine totals unavailable