Setup a bot to auto-update Ishiiruka in this flake when a new update goes out

[lytedev]

I believe this is a pretty common pattern in nixpkgs. A bot is setup such that another project updates, a PR is submitted to nixpkgs when the updated version, hash, etc.

I'm not sure of the specifics, but that would be super useful here, where being out of date means you're not able to play (unless, of course, you know what you're doing, in which case you can clone the flake and update yourself, override it as needed, etc.).

Anyways, just making this issue as a place to focus the discussion!