## Explanation

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## References

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## Checklist

- [ ] I've updated the test suite for new or updated code as appropriate
- [ ] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [ ] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/processes/updating-changelogs.md)
- [ ] I've introduced [breaking
changes](https://github.com/MetaMask/core/tree/main/docs/processes/breaking-changes.md)
in this PR and have prepared draft pull requests for clients and
consumer packages to resolve them

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Test-only refactor and devDependency cleanup; production code paths
are unchanged.
> 
> **Overview**
> Removes the `sinon` devDependency from
`@metamask/composable-controller` (and the corresponding `yarn.lock`
entry).
> 
> Updates `ComposableController.test.ts` to replace `sinon.stub()` usage
with `jest.fn()` and switches assertions to Jest call tracking,
eliminating the `sinon.restore()` cleanup hook.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
4496003. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->