feature: add functionality to restore from backup

[faekiva]

I'm not seeing anything in the docs around how to restore from the backups this application is making, I'm guessing it's just expected to use the restic CLI separately? Potentially interested in contributing this functionality but I wanted to make sure there wasn't already a really clean way of doing it I was missing.

[lawndoc]

Yep, currently restores need the restic CLI. This feature was already something I was considering adding! If you want to collaborate, that would be great! I'll open up discussions on this repo and let's create a thread there to talk about what the implementation should look like.

[lawndoc]

Please use #8 as an open forum to discuss ideas about what the restore functionality should look like. We will use this issue to provide decision announcements and timeline updates related to this feature.