アクティビティフィードの作成

{
  "message.id": "f3c9cd09-10d7-4f59-b9bc-66e16607f1d5",
  "message.name": "the-name-you-set",
  "message.title": "Claim 50% Off Today", // email subject example
  "message.title": "{'en':'the message title/headings'}", // push title example
  "message.contents": "{'en':'the message content'}",
  "message.template_id": "the-template-uuid-if-set",
  "message.url": "the-message-url",
  "message.app_url": "the-message-app-url",
  "message.web_url": "the-message-web-url"
}