Merge branch 'main' into glitch-soc/merge-upstream

Conflicts:
- `README.md`:
  Minor upstream change, our README is completely different.
  Kept ours.
- `lib/tasks/assets.rake`:
  glitch-soc has extra code to deal with its theming system,
  upstream changed a line that exists in glitch-soc.
  Applied upstream changes.

app/serializers/rest/instance_serializer.rb

@@ -45,6 +45,7 @@ class REST::InstanceSerializer < ActiveModel::Serializer
     {
       urls: {
         streaming: Rails.configuration.x.streaming_api_base_url,
+        status: object.status_page_url,
       },
 
       accounts: {
@@ -97,8 +98,6 @@ class REST::InstanceSerializer < ActiveModel::Serializer
   def registrations_message
     if Setting.closed_registrations_message.present?
       markdown.render(Setting.closed_registrations_message)
-    else
-      nil
     end
   end