DEV: Make lazy_load_categories setting use groups (#25282)

This allows certain users to test the new feature and avoid disruptions
in other's workflows.

config/locales/server.en.yml

@@ -2503,6 +2503,7 @@ en:
 
     experimental_form_templates: "EXPERIMENTAL: Enable the form templates feature. <b>After enabled,</b> manage the templates at <a href='%{base_path}/admin/customize/form-templates'>Customize / Templates</a>."
     admin_sidebar_enabled_groups: "EXPERIMENTAL: Enable sidebar navigation for the admin UI for the specified groups, which replaces the top-level admin navigation buttons."
+    lazy_load_categories_groups: "EXPERIMENTAL: Lazy load category information only for users of these groups. This improves performance on sites with many categories."
 
     page_loading_indicator: "Configure the loading indicator which appears during page navigations within Discourse. 'Spinner' is a full page indicator. 'Slider' shows a narrow bar at the top of the screen."
     show_user_menu_avatars: "Show user avatars in the user menu"

config/site_settings.yml

@@ -2328,10 +2328,10 @@ developer:
     default: ""
     allow_any: false
     refresh: true
-  lazy_load_categories:
-    default: false
-    client: true
-    hidden: true
+  lazy_load_categories_groups:
+    default: ""
+    type: group_list
+    list_type: compact
   warn_critical_js_deprecations:
     default: true
     client: true