Maintenance/Bringup GUI

It would be super-helpful to have a boilerplate GUI to be able to interact with the device and make sure everything is working correctly. Let's think of this as a "maintenance-mode" GUI with super-minimal dependencies that can live in this repository.

From this GUI it would be nice to:
* create simple waveforms: (sine, square, triangle)
* get a preview of what this waveform looks like
* save these waveforms to disk, or upload them directly to a connected quac board.
* Generate corresponding hashes for these waveforms
* Start/Pause/Stop each waveform
* read waveform hashes from the device
* read ("aka: download") waveforms back from the device.