git_ui: Add branch picker filter menu (#60857)

# Objective

Make branch filtering consistent and more flexible across the title bar
and Git panel branch pickers.

## Solution

- Replace the remote-only filter toggle with a dropdown for all, local,
and remote branches.
- Preserve the selected filter across branch picker instances.
- Add a ListFilter icon and active-filter indicator.
- Prevent nested filter-menu interactions from dismissing the parent
picker.
- Cycle through all, local, and remote filters with the existing
keyboard shortcut.

## Testing

- Ran `cargo check -p git_ui --tests --no-default-features`.
- Verified formatting with `cargo fmt -p git_ui`.
- Manually checked the filter dropdown from the title bar and Git panel.

## Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] 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)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

## Showcase

- Filters: All, Local, Remote
- "Cmd + Shift + I" to cycle over the filters

<details>
  <summary>New Branch Picker Filter Dropdown</summary>
  
<img width="1624" height="1030" alt="Screenshot 2026-07-12 at 3 53
30 PM"
src="https://github.com/user-attachments/assets/1323d9c9-f4b9-41ee-ba93-841299872c02"
/>

<img width="1624" height="1030" alt="Screenshot 2026-07-12 at 3 54
35 PM"
src="https://github.com/user-attachments/assets/839345ff-de3b-48f0-b4e7-0f8d27e94204"
/>

</details>


Release Notes:

- Improved branch filtering with local, remote, and all-branch options
in the branch picker.
94597a97cbSathwik Chirivelli committed on 7/12/2026, 9:29:44 PM· committed by GitHubparent2211663
5 files changedLine totals unavailable