git_ui: prevent branch name overflow in git details pane (#62665)

# Objective

- prevent branch name overflow in git details pane
- Fixes #62526 

## Solution

- set min width
- add tooltip for readability

## Testing

- manual testing

## Self-Review Checklist:

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

## Showcase
### before
- 
<img width="670" height="205" alt="image"
src="https://github.com/user-attachments/assets/26716b50-6f09-40c1-bec5-d78bd913d4ec"
/>

- No tooltip

### After
- 
<img width="499" height="203" alt="image"
src="https://github.com/user-attachments/assets/3eee21e8-f9e8-4c30-a21d-0c23bf25c9de"
/>

- Tooltip: 

<img width="609" height="364" alt="image"
src="https://github.com/user-attachments/assets/822d784d-889e-4d26-b8e6-de46f8206569"
/>

---

Release Notes:

- N/A or Added/Fixed/Improved ...
56b1e79a55AbdAlRahman Gad committed on 8/15/2026, 3:13:04 PM· committed by GitHubparent1e3d8b5
1 file changedLine totals unavailable