curl --request GET \
  --url https://api.mixpeek.com/v1/apps/{app_id}/users

{
  "users": [
    {
      "user_id": "<string>",
      "membership_id": "<string>",
      "role": "<string>",
      "email": "<string>",
      "name": "<string>",
      "avatar_url": "<string>",
      "joined_at": "<string>"
    }
  ],
  "total": 123
}