Slack-inspired mobile-first messaging interface with:
- Main inbox with tab navigation (All, @Mentions, DMs, Channels)
- Slide-in sidebar menu with channels and portal links
- Full conversation view with message bubbles, reactions, typing indicators
- Thread/channel drill-down with compose bar
- Touch gestures (swipe to close sidebar/threads)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
