List categories

curl --request GET \
  --url https://integrations.clopos.com/open-api/v2/categories \
  --header 'x-token: <api-key>'

{
  "success": true,
  "data": [
    {
      "id": 123,
      "parent_id": 123,
      "name": "<string>",
      "slug": "<string>",
      "color": "<string>",
      "status": 123,
      "depth": 123,
      "_lft": 123,
      "_rgt": 123,
      "properties": {},
      "children": "<array>",
      "created_at": "2023-11-07T05:31:56Z",
      "updated_at": "2023-11-07T05:31:56Z"
    }
  ],
  "total": 123,
  "time": 123,
  "timestamp": "2023-11-07T05:31:56Z",
  "unix": 123
}