Add notifications for new reports (#18697)

app/serializers/rest/report_serializer.rb

@@ -1,7 +1,10 @@
 # frozen_string_literal: true
 
 class REST::ReportSerializer < ActiveModel::Serializer
-  attributes :id, :action_taken
+  attributes :id, :action_taken, :action_taken_at, :category, :comment,
+             :forwarded, :created_at, :status_ids, :rule_ids
+
+  has_one :target_account, serializer: REST::AccountSerializer
 
   def id
     object.id.to_s