DEV: Migrate sidebar site settings (#19336)

This new site setting replaces the
`enable_experimental_sidebar_hamburger` and `enable_sidebar` site
settings as the sidebar feature exits the experimental phase.

Note that we're replacing this without depreciation since the previous
site setting was considered experimental.

Internal Ref: /t/86563

app/serializers/concerns/user_sidebar_tags_mixin.rb

@@ -26,6 +26,6 @@ module UserSidebarTagsMixin
   end
 
   def include_display_sidebar_tags?
-    SiteSetting.tagging_enabled && SiteSetting.enable_experimental_sidebar_hamburger
+    SiteSetting.tagging_enabled && !SiteSetting.legacy_navigation_menu?
   end
 end

app/serializers/current_user_serializer.rb

@@ -258,7 +258,7 @@ class CurrentUserSerializer < BasicUserSerializer
   end
 
   def include_sidebar_category_ids?
-    SiteSetting.enable_experimental_sidebar_hamburger
+    !SiteSetting.legacy_navigation_menu?
   end
 
   def include_status?

app/serializers/site_serializer.rb

@@ -243,7 +243,7 @@ class SiteSerializer < ApplicationSerializer
   end
 
   def include_anonymous_default_sidebar_tags?
-    scope.anonymous? && SiteSetting.enable_experimental_sidebar_hamburger && SiteSetting.tagging_enabled && SiteSetting.default_sidebar_tags.present?
+    scope.anonymous? && !SiteSetting.legacy_navigation_menu? && SiteSetting.tagging_enabled && SiteSetting.default_sidebar_tags.present?
   end
 
   private