Add E2EE API (#13820)

app/serializers/rest/keys/claim_result_serializer.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class REST::Keys::ClaimResultSerializer < ActiveModel::Serializer
+  attributes :account_id, :device_id, :key_id, :key, :signature
+
+  def account_id
+    object.account.id.to_s
+  end
+end