Extract "surface-control" management into new option-enabled module

microsoft/surface/common/default.nix

@@ -7,6 +7,7 @@ in {
   imports = [
     ./kernel
     ./ipts
+    ./surface-control
   ];
 
   microsoft-surface.kernelVersion = mkDefault "6.0.11";

microsoft/surface/common/surface-control/default.nix

@@ -0,0 +1,25 @@
+{ config, lib, pkgs, ... }:
+
+
+let
+  inherit (lib) mkDefault mkEnableOption mkIf mkMerge;
+
+  cfg = config.microsoft-surface.surface-control;
+
+in {
+  options.microsoft-surface.surface-control = {
+    enable = mkEnableOption "Enable 'surface-control' for Microsoft Surface";
+  };
+
+  config = mkMerge [
+    {
+      microsoft-surface.surface-control.enable = mkDefault false;
+    }
+
+    (mkIf cfg.enable {
+      environment.systemPackages = with pkgs; [ surface-control ];
+      services.udev.packages = with pkgs; [ surface-control];
+      users.groups.surface-control = { };
+    })
+  ];
+}

microsoft/surface/default.nix

@@ -17,13 +17,6 @@ in {
     options iwldvm force_cam=N
   '';
 
-  environment.systemPackages = [
+  microsoft-surface.surface-control.enable = true;
-    pkgs.surface-control
-  ];
-  users.groups.surface-control = { };
-  services.udev.packages = [
-    pkgs.surface-control
-  ];
-
   microsoft-surface.ipts.enable = true;
 }