ADC now works in interrupt mode. No idea why DMA was unreliable.
Initial button push / release detection and mode switch detection working. No callbacks implemented yet.
ADC is sort of functioning, but not reliably. LEDs are sort of working. Buzzer isn't working right and is nearly always on as I can't set the PF2 mode.
Builds, but is not yet usable in any way nor is anything tested.
This includes ADC reading, basic RGBLED control, and init code. Still need to do probe, user IO including mode select and settings, RGBLED programs, and more.