curl --request GET \
  --url https://core.ravenna.ai/api/request-type-custom-fields/{id} \
  --header 'x-ravenna-api-token: <api-key>'

{
  "id": "<string>",
  "order": 123,
  "private": true,
  "requestTypeId": "<string>",
  "customField": {
    "id": "<string>",
    "workspaceId": "<string>",
    "key": "<string>",
    "label": "<string>",
    "description": "<string>",
    "required": true,
    "system": true,
    "config": null,
    "type": "TEXT",
    "options": [
      {
        "id": "<string>",
        "value": "<string>",
        "order": 123,
        "description": "<string>",
        "color": "<string>",
        "icon": "<string>",
        "customFieldId": "<string>",
        "createdAt": "<string>",
        "updatedAt": "<string>"
      }
    ],
    "createdAt": "<string>",
    "updatedAt": "<string>",
    "_count": {
      "requestTypeCustomField": 123
    }
  },
  "customFieldId": "<string>",
  "ticketField": "TITLE",
  "required": true,
  "createdAt": "<string>",
  "updatedAt": "<string>",
  "parentId": "<string>"
}