Revamp notification policy options (#31343)

app/serializers/rest/v1/notification_policy_serializer.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+class REST::V1::NotificationPolicySerializer < ActiveModel::Serializer
+  attributes :filter_not_following,
+             :filter_not_followers,
+             :filter_new_accounts,
+             :filter_private_mentions,
+             :summary
+
+  def summary
+    {
+      pending_requests_count: object.pending_requests_count.to_i,
+      pending_notifications_count: object.pending_notifications_count.to_i,
+    }
+  end
+
+  def filter_not_following
+    !object.accept_not_following?
+  end
+
+  def filter_not_followers
+    !object.accept_not_followers?
+  end
+
+  def filter_new_accounts
+    !object.accept_new_accounts?
+  end
+
+  def filter_private_mentions
+    !object.accept_private_mentions?
+  end
+end