Add dconf support

modules/desktop/gnome.nix

@@ -15,11 +15,30 @@ in {
       desktopManager.gnome.enable = true;
     };
 
+    programs.dconf.enable = true;
+    dconf.settings = {
+      "org/gnome/shell" = {
+        favorite-apps = [
+          "firefox.desktop"
+          "org.gnome.Nautilus.desktop"
+          "org.gnome.Console.desktop"
+        ];
+      };
+      "org/gnome/desktop/background" = {
+        picture-uri = "file://${pkgs.gnome.gnome-backgrounds}/share/backgrounds/gnome/adwaita-l.webp";
+        picture-uri-dark = "file://${pkgs.gnome.gnome-backgrounds}/share/backgrounds/gnome/adwaita-d.webp";
+      };
+    };
+
     fonts.fonts = with pkgs; [
       noto-fonts
       ubuntu_font_family
     ];
 
+    user.packages = with pkgs; [
+      celluloid
+    ];
+
     environment.systemPackages = with pkgs; [
       bind
       bmon