debugger: Update debug panel when breakpoint store changes (#63240)

# Objective

- There is currently a bug where toggling breakpoints would not be
immediately reflected in the breakpoint list of the debug panel
- For example, pressing `F9` to create a breakpoint would not
immediately add an entry to the breakpoints list in the debug panel,
instead requiring another event like mouse movement

## Solution

- Subscribe the debug panel to changes to the breakpoint store.

## Testing

- Manually tested

## 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


https://github.com/user-attachments/assets/d2b7efab-0131-491e-8339-3657edaf7fcd



https://github.com/user-attachments/assets/4161a435-c59e-4f6a-9387-31528c127c80





---

Release Notes:

- Fixed debugger panel not immediately reflecting changes in toggled
breakpoints
45cd77bba0Casey Avila committed on 8/26/2026, 10:17:48 AM· committed by GitHubparent1f7eae7
1 file changedLine totals unavailable