Agentic UI: Make the site identity a menu with start/stop and quick actions

[shaunandrews]

Related issues

• STU-2162

⚠️ Visual change: needs human review in light + dark mode.

How AI was used in this PR

AI built the menu and the masked-dot treatment to the design direction set in the exploration.

Proposed Changes

Make the header identity interactive.

• The site icon + name + address become one button opening a site menu: Start/Stop site (via the shared toggle hook from the bottom of this stack), Open in browser, and the Local address.
• A run-state dot is masked into the icon's corner — a genuine CSS-mask cutout, not a drawn ring — shown only when the sidebar is hidden (the sidebar rows already carry status). Green running, grey stopped, blue blinking transitioning; respects prefers-reduced-motion.

Screenshots

Site menu · light	Site menu · dark

Masked status dot

Testing Instructions

1. Click the header identity — the menu opens; Start/Stop toggles the site; Open in browser disables when stopped.
2. Hide the sidebar — the dot appears on the icon, centred on the address line; show it and the dot disappears.
3. Light + dark appearance; console clean.

Verification completed

• npm run typecheck · toolbar suite passes

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?