curl -X GET "https://your-collabase.ch/api/v1/search/fields?entity=task" \
  -H "Authorization: Bearer cb_xYz123ABCD..."

{
  "data": {
    "fields": [
      {
        "key": "dueDate",
        "origin": "system",
        "label": null,
        "valueType": "date",
        "operators": ["eq", "gt", "gte", "lt", "lte", "is_empty", "is_not_empty"],
        "sortable": true,
        "columnable": true,
        "groupable": true,
        "summable": false,
        "options": null
      }
    ]
  }
}