Working CircuitMess Chatter V2.1 Meshtastic port

[morrisoncarter2010-web]

My dad and I have a working Meshtastic port for the newer green PCB CircuitMess Chatter V2.1, tested on two physical devices.

LoRa messaging, BLE, the ST7735S display, physical 12-key keyboard/multi-tap input, battery monitoring, brightness, and screen color controls are working.

The hardware differs substantially from the Chatter currently supported by Meshtastic, so we've implemented it as a separate chatter2-v21 variant.

The working implementation and documentation are public here:

https://github.com/morrisoncarter2010-web/Chatter-Meshtastic

I've also posted the technical details in the firmware repository Discussions. We're interested in contributing the V2.1 support upstream and would appreciate guidance from the firmware maintainers on the preferred next step.