feat(mobile): mobile UX polish with bottom sheet, haptics, gestures, PWA (M16.1-M16.10)
- BottomSheet.vue: gesture-driven with 40/80/100% snap points, backdrop
- Swipe navigation: left/right to switch conversations, 80px threshold
- Pull-to-refresh: custom glass spinner, haptic on release
- Haptic feedback: useHaptics() composable with pattern presets
- Web Share API: native share with glass fallback sheet
- Pinch-to-zoom: usePinchZoom() composable, 1x-4x, double-tap reset
- iOS PWA: safe area insets CSS utilities, black-translucent status bar
- Long-press context menus: 500ms trigger via bottom sheet
- Scroll position memory: per-route Map, auto-restore on mount
- Landscape mode: CSS split layout, orientation change detection
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
