A console diagnostic that opens the RIO COM port, runs the real serial link,
and logs every event (buttons, keypad, axis, version/check, control bytes,
framing). Flashes all lamps once to prove the PC->RIO path and echoes a lamp
on each button press. Verified end-to-end against a partial RIO on COM1
(firmware 4.2; MFD + keypad inputs and the throttle axis all decode).
dotnet run --project tools/RioSerialMonitor -- COM1 30
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>