add nova-plugin: in-process cxx-qt stats plugin replacing nova-stats subprocess

nix/package.nix

@@ -6,6 +6,7 @@
   quickshell,
   nova-stats,
   nova-shaders,
+  nova-plugin,
   glib,
 }:
 let
@@ -38,6 +39,7 @@ symlinkJoin {
   paths = [
     shell
     nova-shaders
+    nova-plugin
   ];
 
   nativeBuildInputs = [ makeWrapper ];
@@ -46,6 +48,7 @@ symlinkJoin {
     mkdir -p $out/bin
     makeWrapper ${lib.getExe quickshell} $out/bin/nova-shell \
       --add-flags "-p $out/share/nova-shell/shell.qml" \
+      --add-flags "-I $out/lib/qt-6/qml" \
       --prefix PATH : ${
         lib.makeBinPath [
           nova-stats