Prepared a basic desktop version.

You can either use the debian below, or you could run it directly by using:

$ cargo run --bin cardbrick-desktop

User can now:

1. Load an Anki deck
2. Maintain state between sessions
3. Do quick sessions at any time
4. Scroll through missed cards at the end of their session
5. See previous history.

I've confirmed this works on the RG35XX Plus and RG35XX SP devices running Rocknix.

This can be used for testing purposes on different devices. To do so, you will have to create a directory with the decks and run the code to decompress / pre-cache / update databases as necessary. This process will be simplified when we approach the 1.0 release.