back to kde+karousel, niri was cool, but it wasn't kde

aspects/desktop/kde.nix

@@ -33,6 +33,17 @@
           ];
           config.common.default = "*";
         };
+        environment = {
+          systemPackages = with pkgs; [
+            kdePackages.karousel
+            kde-rounded-corners
+          ];
+          plasma6.excludePackages = with pkgs.kdePackages; [
+            elisa
+            gwenview
+            kate
+          ];
+        };
         programs.kdeconnect.enable = true;
       };