feat: switch to automatic nixosConfiguration population

flake.nix

@@ -6,9 +6,6 @@
   };
 
   outputs = inputs: inputs.flake-parts.lib.mkFlake { inherit inputs; }  {
-    systems = [
-      "x86_64-linux"
-    ];
     imports = [
       ./hosts
     ];

hosts/default.nix

@@ -6,15 +6,15 @@ let
     lib.filterAttrs isDirectory (builtins.readDir ./.)
   );
   hosts = lib.genAttrs hostNames (name: {
-    modules = [
+    imports = [
       (./. + "/${name}")
     ];
   });
 in 
 {
-  flake.nixosConfigurations = lib.mapAttrs (host: hostConfig: lib.nixosSystem {
-    inherit (hostConfig) modules;
+  nixosConfigurations = lib.mapAttrs (host: hostConfig: lib.nixosSystem {
     system = "x86_64-linux";
+    modules = hostConfig;
     specialArgs = { inherit inputs; };
   }) hosts;
 }