curl --request GET \
  --url http://localhost/customers \
  --header 'Authorization: Bearer <token>'

{
  "object": "list",
  "items": [
    {
      "object": "customer",
      "id": "cus_<id>",
      "first_name": "John",
      "last_name": "Doe",
      "email": "john.doe@example.com",
      "created_at": "2024-03-14T12:00:00Z",
      "type": "person",
      "vat_id": "DE123456789"
    }
  ]
}