Wire up the new Silo authentication dock panel in InitGui.py:
- _setup_silo_auth_panel() creates the Database Auth dock widget
- Tabified with the existing Database Activity panel on the right dock
- Deferred to 4500ms to ensure activity panel exists first
- Widget reference pinned on the dock panel to prevent GC
Update silo submodule to include auth widget, login flow, token
management, enhanced settings dialog, and silo-auth.svg icon.
36a88d0959