profile/core: convert to nixosModule

profiles/core/default.nix

@@ -1,7 +1,23 @@
-[
-  ./core.nix
-  ./modules.nix
-  ./network.nix
-  ./nix.nix
-  ./users.nix
-]
+{
+  config,
+  lib,
+  pkgs,
+  inputs,
+  ...
+}@args:
+let
+  cfg = config.my.profiles.core;
+in
+{
+  options.my.profiles.core.enable = lib.mkEnableOption "core profile";
+
+  config = lib.mkIf cfg.enable (
+    lib.mkMerge [
+      (import ./core.nix args)
+      (import ./modules.nix args)
+      (import ./network.nix args)
+      (import ./nix.nix args)
+      (import ./users.nix args)
+    ]
+  );
+}