Create a map interface that shows all active needs, offers, and volunteers in real-time. Requirements:
- Map centered on disaster area with clustered markers
- Color-coded pins: red (critical needs), orange (high needs), blue (offers), green (volunteers)
- Filter panel: by category, urgency, type
- Click marker to see details and take action (offer help, confirm match)
- Live updates.new posts appear without page refresh (use Server-Sent Events or polling with 30s interval)
- Offline-capable: cache last known state in localStorage, show stale data warning when offline
- Works on mobile.touch-friendly, minimal UI chrome
Use Leaflet (no API key required) with OpenStreetMap tiles. The map should be usable within 3 seconds on a 3G connection.lazy load non-critical UI.