nix: move all nixos configuration to nixosModules

export them

nix/nixosModules/named/carbon/gui.nix

@@ -0,0 +1,49 @@
+{ pkgs, ... }:
+
+{
+  services.xserver = {
+    enable = true;
+    autoRepeatDelay = 300;
+    autoRepeatInterval = 40;
+
+    windowManager.xmonad = {
+      enable = true;
+      enableContribAndExtras = true;
+    };
+
+    displayManager.lightdm = {
+      enable = true;
+      background = "#000000";
+      greeters.gtk.cursorTheme = {
+        name = "volantes_cursors";
+        package = pkgs.volantes-cursors;
+        size = 64;
+      };
+    };
+  };
+
+  services.xscreensaver.enable = true;
+
+  services.picom = {
+    enable = true;
+    vSync = true;
+    fade = true;
+    fadeDelta = 3;
+    settings.fade-exclude = [
+      "name = 'Fcitx5 Input Window'"
+      "class_g = 'fcitx'"
+      "class_i = 'fcitx'"
+    ];
+  };
+
+  services.libinput = {
+    mouse = {
+      naturalScrolling = true;
+      accelSpeed = "-0.5";
+    };
+    touchpad = {
+      naturalScrolling = true;
+      tapping = false;
+    };
+  };
+}