The parcel/watcher callback was shared and published all filesystem events
without re-filtering through FileIgnore. Build artifacts and lock files in
ignored directories (out/, .turbo/, etc.) fired watcher events that drove
repeated refreshVcs() calls and made the review panel flicker.
Also fixes the frontend listener to handle absolute .git/worktrees/... paths
produced by git worktrees, which bypassed the old startsWith('.git/') check.
Fixes#21452
036a100f2a