Closes #47007 

After #50974, symlinked `settings.json` can be opened and saved, but the
worktree ends up rooted at the file itself rather than its parent
directory, which causes this error to be logged when changing settings
via the settings GUI:

```
2026-03-18T22:24:05+01:00 ERROR [worktree] ignoring event
"C:\\Users\\Bryan\\dev\\bryanpth\\dotfiles\\config\\zed\\settings.json~RF1ab7ae0.TMP" outside of root path
"C:\\Users\\Bryan\\dev\\bryanpth\\dotfiles\\config\\zed\\settings.json"
```

Fixed by canonicalizing the symlink path before passing to `open_paths`.
Tested with a symlinked settings.json, both directly and through WSL.

Release Notes:
- Fixed incorrect worktree root when settings.json is a symlink on
Windows