#85 feat(navbar): native segment rows under the navbar

Summary

• New segments option on setNavbar: rows of native segments drawn under the bar, top to bottom.
  • iOS: UISegmentedControl (segmented) or horizontally scrolling capsule buttons (scroll, Liquid Glass on iOS 26, filled/gray before).
  • Android: Material-style connected segmented buttons or scrolling filter chips (no new dependency).
  • style: 'auto' picks segmented for ≤4 items, scroll otherwise.
• Rows extend the navbar container, the reported top/navbarHeight insets, the edge blur, and hide-on-scroll distance.
• New navbarSegmentSelect event { groupId, id, index }. Rows keep their views when only selectedId changes, so selection animates and scroll position stays.
• Example app: "Segment rows" toggle in the Navbar playground.

Motivation: Capgo app settings/app pages show web tab rows under the native navbar (half native, half web). This lets apps move those rows into native chrome.

Test plan

• xcodebuild iOS build
• Android compileDebugJavaWithJavac testDebugUnitTest
• bun run build (docgen + tsc + rollup)
• Example app on iPhone 18 Pro simulator (iOS 26)
• Android emulator visual check

🤖 Generated with Claude Code

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Summary by CodeRabbit

• New Features
  • Added configurable segment rows to the navigation bar, with selectable items, optional titles and icons, accessibility labels, and enabled states.
  • Choose segmented controls or horizontally scrolling pills, or let the layout adapt to the number of items. Selecting an item reports its group, item, and position.
  • The example app now demonstrates segment rows and selection behavior.
• Documentation
  • Added API documentation for segment configuration and selection events.