- Fix thread safety: defer Reticulum link callbacks (packet, link_closed)
to call_update() which runs under LVGL lock, preventing crashes from
concurrent LVGL access across cores
- Fix outgoing call signal handling: store link reference and re-register
packet/link_closed callbacks in on_call_link_established so signals
are actually received
- Fix call answer screen freeze: update UI before blocking audio init
(I2S/ES7210/Codec2 setup) so screen renders immediately
- Fix audio direction: use startPlayback() (speaker RX) instead of
startCapture() (mic TX) so received audio is actually heard
- Add msgpack wire format for LXST signalling and audio frames
- Add LXST IN destination for receiving calls + announce support
- Add incoming call UI (Answer/Reject buttons) on CallScreen
- Add path request before outgoing call link establishment
- Add LXST announce handler registration
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Add CallScreen with ring/active/ended states and call controls
- Add call state machine to UIManager (link establish, identify, ring, answer)
- Add call button to ChatScreen header
- Add call initiate/hangup with Reticulum Link management
- Add StatusScreen call status display
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
