Summary

• Bound the desktop chrome tab strip container so tabs stay clipped to the available chrome area.
• Keep themed chrome tab lists capped at max-width: 100% instead of allowing max-width: none to override the available area.
• Pin the macOS command-search button as a fixed chrome tool next to the right panel toggle, so opening the right dock does not drag the search button left or unnecessarily reduce tab capacity.
• Extend the focused AppChrome tab regression test to cover overflow clipping, bounded themed tab lists, and fixed macOS chrome tools.

Root Cause

PR #4422 reserved the right dock width in the chrome padding, but the themed tab list still allowed max-width: none. That avoided some overlap but made the macOS chrome treat the right dock as unavailable tab space. With enough open tabs, the command-search button could move with the tab flow instead of staying fixed beside the right panel toggle.

Solution

The tab strip is now bounded and scrollable, while macOS renders command search as a fixed chrome tool. macOS chrome padding reserves only the fixed search and panel-toggle controls, so the tab strip can use the full top chrome width even when the right dock is open.

Verification

• npm run check:css
• npx tsx src/__tests__/app-chrome-tabs.test.ts
• git diff --check origin/main-v2...HEAD