Refactor formatter (#17828)

* Refactor formatter

* Move custom emoji pre-rendering logic to view helpers

* Move more methods out of Formatter

* Fix code style issues

* Remove Formatter

* Add inline poll options to RSS feeds

* Remove unused helper method

* Fix code style issues

* Various fixes and improvements

* Fix test

app/serializers/activitypub/note_serializer.rb

@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 class ActivityPub::NoteSerializer < ActivityPub::Serializer
+  include FormattingHelper
+
   context_extensions :atom_uri, :conversation, :sensitive, :voters_count
 
   attributes :id, :type, :summary,
@@ -39,11 +41,11 @@ class ActivityPub::NoteSerializer < ActivityPub::Serializer
   end
 
   def content
-    Formatter.instance.format(object)
+    status_content_format(object)
   end
 
   def content_map
-    { object.language => Formatter.instance.format(object) }
+    { object.language => content }
   end
 
   def replies