* Add "+" menu button to horizontal tab bar for new terminal/browser tabs
Adds a "+" button to the tab bar (next to split buttons) that shows a
dropdown menu with "New Terminal ⌘T" and "New Browser ⌘⇧L" options.
- Uses native NSButton + NSMenu so the icon matches the split buttons
- Menu appears below the button
- Routes tab creation through new didRequestNewTab delegate method
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* works
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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
