curl --request GET \
  --url https://api.getoutbox.ai/contacts/list \
  --header 'Authorization: <api-key>'

{
  "results": [
    {
      "id": "<string>",
      "name": "<string>",
      "email": "<string>",
      "phone": "<string>",
      "tags": [
        "<string>"
      ],
      "last_activity": "2023-11-07T05:31:56Z",
      "created_at": "2023-11-07T05:31:56Z"
    }
  ],
  "total": 123
}