End-to-end testing in a VM

[ifd3f]

Is your feature request related to a problem? Please describe.

This should improve the pipeline by making it so that we're certain the code changes don't break things.

Describe the solution you'd like

An end-to-end NixOS test that does the following:

• Spawn a VM with a USB
• Run caligula in a tmux session
• Send inputs to caligula in tmux
• Preferably, also takes a dump of the output on both success and failure

Describe alternatives you've considered

• Running it outside of a NixOS test, as a script that invokes QEMU

Additional context

N/A