Image building take 2

We want verity protected partitions as well as encrypted state/data along with verified boot.
This PR integrates Peter Marshall's awesome little Nixlet project as a starting point, especially the nice testing scaffolding will be super helpful! ✨

https://github.com/petm5/nixlet/

justfile

@@ -13,11 +13,7 @@ build: build-image
 
 # Build PatOS image
 build-image:
-  nix build .#patos_image
-
-# Build PatOS update image
-build-update:
-  nix build .#patos_update
+  nix build .#patos
 
 run: build-image
-  qemu-efi -snapshot ./result/disk.qcow2
+  qemu-uefi-tpm ./result/*.img