Add E2EE API (#13820)

app/serializers/rest/keys/query_result_serializer.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class REST::Keys::QueryResultSerializer < ActiveModel::Serializer
+  attributes :account_id
+
+  has_many :devices, serializer: REST::Keys::DeviceSerializer
+
+  def account_id
+    object.account.id.to_s
+  end
+end