List credential references

curl --request GET \
  --url https://api.getmillwork.dev/v1/credentials \
  --header 'Authorization: Bearer <token>'

const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://api.getmillwork.dev/v1/credentials', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "credentials": [
    {
      "created_at": "2023-11-07T05:31:56Z",
      "credential_ref": "<string>",
      "display_name": "<string>"
    }
  ]
}

{
  "instance": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "status": 123,
  "title": "<string>",
  "type": "<string>",
  "detail": "<string>",
  "errors": [
    {
      "field": "<string>",
      "message": "<string>"
    }
  ],
  "retry_after_s": 123
}

{
  "instance": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "status": 123,
  "title": "<string>",
  "type": "<string>",
  "detail": "<string>",
  "errors": [
    {
      "field": "<string>",
      "message": "<string>"
    }
  ],
  "retry_after_s": 123
}