feat: replace impermanence with preservation (#198)

* feat: replace impermanence with preservation

* fix: This module cannot be used with scripted initrd.

* fix: permission for /var/lib/private

* chore: boot.initrd.systemd.enable

* docs: boot.initrd.luks.devices.<name>.fallbackToPassword is implied by systemd stage 1

* fix: typo

nixos-installer/flake.nix

@@ -34,7 +34,7 @@
           ../modules/nixos/base/networking.nix
 
           ../hosts/idols-ai/hardware-configuration.nix
-          ../hosts/idols-ai/impermanence.nix
+          ../hosts/idols-ai/preservation.nix
         ];
       };
 
@@ -64,7 +64,7 @@
           ../modules/nixos/base/networking.nix
 
           ../hosts/12kingdoms-shoukei/hardware-configuration.nix
-          ../hosts/idols-ai/impermanence.nix
+          ../hosts/idols-ai/preservation.nix
         ];
       };
     };