This PR adds the diff stat numbers to the `git: branch diff` view
toolbar.
<img width="550" height="1964" alt="Screenshot 2026-02-20 at 10 58@2x"
src="https://github.com/user-attachments/assets/0fc63b64-ce6e-417a-92b5-8008f2561a8f"
/>
---
Before you mark this PR as ready for review, make sure that you have:
- [x] Added a solid test coverage and/or screenshots from doing manual
testing
- [x] Done a self-review taking into account security and performance
aspects
- [x] Aligned any UI changes with the [UI
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
Release Notes:
- Git: Added diff stat numbers to the Branch Diff (`git: branch diff`)
view.