Get categories

curl --request GET \
  --url https://app.herondata.io/api/categories \
  --header 'x-api-key: <api-key>'

{
  "categories": [
    {
      "analytics_group": "revenue",
      "created": "2025-06-19T18:49:41.133480",
      "description": "Rent for offices, workspaces or storage facilities",
      "heron_id": "ctg_AjWKMcC9V8DGVDyZiiKxk5",
      "label": "Rent"
    }
  ]
}