workstation-v0: extend aggregate polish helper with dock and shortcut signals

Closed as completed by PR #147.

Resolution:
- `check-workstation-polish.sh` now aggregates shortcut-map and GNOME dock/extension signals.
- `.github/workflows/workstation-polish-validation.yml` validates the expanded aggregate surface.
- Issue #145 carried the same bounded work packet and was also closed by #147.

No additional work remains under this duplicate issue.