Airspy support:
- Add AIRSPY to SDRType enum and driver mappings
- Create AirspyCommandBuilder using SoapySDR tools (rx_fm, readsb, rtl_433)
- Register in SDRFactory and add to hardware type dropdown
- Supports Airspy R2/Mini (24MHz-1.8GHz) and HF+ devices
GPS coordinate persistence:
- Save observer location to localStorage when manually entered or via geolocation
- Restore saved coordinates on page load in both index.html and adsb_dashboard.html
- Coordinates are shared between both pages
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
