refactor: remove forum and topic feature chains

src/Admin/ExtensionController.php

@@ -92,7 +92,6 @@ class ExtensionController extends ControllerBase {
             'data' => [
                 'total'         => 0,
                 'nav_count'     => 0,
-                'special_count' => 0,
             ],
         ]);
     }