Feature: Monitor control using DDC/CI protocol

[njreid]

First - huge kudos for this project. So awesome! Thanks so much for all your work on it @jfedor2.

I bought the little Waveshare 2040 zero board, and it has a mini HDMI connector. It's not well known, but you can control parameters for many monitors via the DDC/CI protocol, even when the interface isn't active. (Note, this is different from HDMI-CEC).

So, connect the Waveshare to an unused DVI port on a monitor, and then map keys to adjust the brightness, contrast, and sometimes even change inputs - for a KVM-like experience.

https://github.com/tttttx2/ddcvcp