sidebar: Add another round of refinements (#52101)

- Change the branch button's tooltip to be more accurate given it
displays more stuff than only branches
- Hide the worktree dropdown menu when in a non-Git repo project
- Improve provisioned title truncation
- Remove the plus icon from the "view more" item to improve sidebar's
overall feel
- Remove the always visible "new thread" button but make it visible only
when you're in an empty thread state
- Add worktree icon in the thread item and tooltip with full path
- Space out the worktree name from the branch name in the git picker in
the title bar
- Swap order of views in the git picker to "worktree | branches | stash"
- Improve the "creating worktree" loading indicator

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

Release Notes:

- N/A
e126857732Danilo Leal committed on 3/21/2026, 7:22:32 PM· committed by GitHubparent4a965d1
15 files changedLine totals unavailable