curl --request GET \
  --url https://app.manuscritten.com/api/public/envelope-designs \
  --header 'X-API-KEY: <api-key>'

{
  "data": [
    {
      "id": "1f86a2b9-6b7a-42c5-bb77-7c51a5edfe91",
      "name": "Sobre C5 estándar"
    }
  ]
}