Add KvLibadwaita theme to GNOME

modules/desktop/gnome.nix

@@ -1,4 +1,4 @@
-{ config, lib, pkgs, ... }:
+{ config, inputs, lib, pkgs, ... }:
 
 let cfg = config.modules.desktop.gnome;
 in {
@@ -164,6 +164,18 @@ in {
       };
     };
 
+    environment.sessionVariables = {
+      QT_STYLE_OVERRIDE = lib.mkForce "kvantum";
+      QT_WAYLAND_DECORATION = lib.mkForce "adwaita";
+    };
+
+    home.configFile = {
+      "Kvantum/kvantum.kvconfig".text = lib.generators.toINI {} {
+        General.theme = "KvLibadwaitaDark";
+      };
+      "Kvantum/KvLibadwaita".source = "${inputs.kvlibadwaita}/src/KvLibadwaita";
+    };
+
     user.packages = with pkgs; [
       authenticator
       # bottles
@@ -219,7 +231,11 @@ in {
       # gnomeExtensions.window-is-ready-remover
       # gnomeExtensions.worksets
       # gnomeExtensions.workspace-matrix
+      unstable.kdePackages.qtstyleplugin-kvantum
+      unstable.libsForQt5.qtstyleplugin-kvantum
       unstable.morewaita-icon-theme
+      unstable.qadwaitadecorations
+      unstable.qadwaitadecorations-qt6
     ] ++ (if config.virtualisation.podman.enable then [
       pods
     ] else []);