[jedisdead666]

Summary

• add Android G106/G106C profiles with CI-V address 0x70, 19,200 baud, and the required CAT PTT keepalive
• add a focused desktop G106 direct-CI-V backend and a pinned rig-picker option
• prevent DE-19 hardware PTT assertion by requesting DTR low on open and explicitly clearing both DTR and RTS before CAT initialization and on close
• fail the connection unless CAT PTT-off succeeds before mode/frequency setup
• label generic ALSA C-Media devices as DE-19 audio choices and document Linux dependencies/setup
• disable the unsafe desktop receive DT auto-calibration introduced before 0.1.2
• clear legacy rx_offset_ms values at startup and anchor decode/waterfall windows to UTC slots

Field bugs fixed

• Linux serial open could assert a DE-19 hardware PTT line and key the G106 immediately
• rx_offset_ms=-4000 could prevent every decode after restart
• a successful cycle at DT +0.7 to +1.0 could save approximately +528 ms, chop the next slot leading sync block, and prevent later decodes

Safety and timing regression coverage

• verifies G106 CAT PTT on/off frame polarity
• verifies both DTR and RTS are released, including when the first release fails
• verifies PTT-off happens before data-mode initialization and failure rejects the connection
• verifies the 1 Hz keepalive is limited to keyed radios that require it
• verifies legacy -4000 and +528 RX offsets reset to zero on restart
• verifies a decoded batch at DT +0.7 through +1.0 cannot move future receive windows

Verification

• frontend: 33 tests passed; production TypeScript/Vite build passed
• Rust: 135 tests passed (124 library, 9 binary, 2 integration)
• version 0.1.2 AppImage built, extracted, and launched from an isolated empty profile
• packaged runtime reset a deliberately seeded rx_offset_ms=-4000 to zero on restart
• Android unit tests are included; local execution is unavailable because this Linux host has no Android SDK configured