Closes (#1817)



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## Summary by cubic
Fixes the bug where editing a custom model didn’t update the currently
selected model. The selection now stays in sync after renaming or
editing.

- **Bug Fixes**
- Use useSettings to detect if the edited model is the active one (match
provider and apiName).
- Update settings.selectedModel with the new apiName; on failure show an
error and keep the dialog open; otherwise show success, call onSuccess,
then close.

<sup>Written for commit 88045165a3989277e703a8f31712fcf1dfeaa32a.
Summary will update automatically on new commits.</sup>

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