Migrated from import based to config based

modules/system/display-managers/default.nix

@@ -0,0 +1,21 @@
+{ lib, ... }:
+
+with lib;
+
+let
+  cfg = config.settings.display-manager;
+in {
+  options = {
+    settings.display-manager = lib.mkOption {
+      type = lib.types.enum ["sddm" "cosmic-greeter"];  
+      description = ''
+        Specify which display manager to use
+      '';
+    };
+  };
+
+  imports = [
+    ./sddm.nix
+    ./cosmic-greeter.nix
+  ];
+}