Closes#40602
### Summary
This PR ensures that active debug lines only open in a single pane and
new active debug lines are added to the most recent pane that contained
an active debug line. This fixes a bug where Zed could go to the active
debug line file and location in every pane a user had open, even if that
pane was focused on a different file.
I fixed this by storing the `entity_id` of the pane containing the most
recently active debug line on `BreakpointStore`, this is consistent with
where the selected stack frame is stored. I used an `entity_id` instead
of a strong type to avoid circular dependencies. Whenever an active
debug line is being set in the editor or by the debugger it now checks
if there's a specific pane it should be set in, and after setting the
line it updates `BreakpointStore` state.
I also added a new method on the `workspace::Item` trait called `fn
pane_changed(&mut self, new_pane_id: EntityId, cx: &mut Context<Self>)`
To enable `Editor` to update `BreakpointStore`'s active debug line pane
id whenever an `Editor` is moved to a new pane.
### PR review TODO list
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:
- debugger: Fix bug where active debug lines could be set in the wrong
pane
Anthony Eid
61548ce614