feat(desktop): configure system themes and cursors

modules/hm/desktop/cursor.nix

@@ -1,11 +0,0 @@
-{
-  flake.modules.homeManager.desktop =
-    { pkgs, ... }:
-    {
-      home.pointerCursor = {
-        package = pkgs.bibata-cursors;
-        name = "Bibata-Modern-Ice";
-        size = 28;
-      };
-    };
-}

modules/hm/desktop/theme.nix

@@ -0,0 +1,31 @@
+{
+  flake.modules.homeManager.desktop =
+    { pkgs, ... }:
+    {
+      home.pointerCursor = {
+        package = pkgs.bibata-cursors;
+        name = "Bibata-Modern-Ice";
+        size = 28;
+      };
+
+      qt = {
+        enable = true;
+        style = {
+          name = "Breeze";
+          package = pkgs.kdePackages.breeze;
+        };
+      };
+
+      gtk = {
+        enable = true;
+        theme = {
+          name = "Materia-dark";
+          package = pkgs.materia-theme;
+        };
+        iconTheme = {
+          package = pkgs.tela-icon-theme;
+          name = "Tela-black";
+        };
+      };
+    };
+}