backend rewrite cont, rebrand

data/resources/ui/window.blp

@@ -1,10 +1,10 @@
 using Gtk 4.0;
 using Adw 1;
 
-template $GnomeframeWindow: Adw.ApplicationWindow {
+template $VoidManifestWindow: Adw.ApplicationWindow {
   default-width: 800;
   default-height: 600;
-  title: "Gnomeframe";
+  title: "VoidManifest";
 
   content:
     // Scaffolding
@@ -66,7 +66,7 @@ menu primary_menu {
     }
 
     item {
-      label: _("_About Gnomeframe");
+      label: _("_About VoidManifest");
       action: "app.about";
     }
   }