curl --request GET \
  --url https://{cluster}.voucherify.io/v1/templates/campaigns \
  --header 'Authorization: Bearer <token>' \
  --header 'X-App-Id: <api-key>' \
  --header 'X-App-Token: <api-key>'

{
  "object": "list",
  "data_ref": "campaign_templates",
  "campaign_templates": [
    {
      "id": "camp_tpl_hFK6hpVc9WKsWaBv4mz7uZn8",
      "name": "DISCOUNT-CAMPAIGN-TEMPLATE",
      "description": "New discount for Q4",
      "campaign_type": "DISCOUNT_COUPONS",
      "created_at": "2024-06-21T13:03:09.431Z",
      "object": "campaign_template"
    },
    {
      "id": "camp_tpl_cR8va5Ga2nAi4Nxoi1I1qR8S",
      "name": "GIFT-CAMPAIGN-TEMPLATE",
      "campaign_type": "GIFT_VOUCHERS",
      "created_at": "2024-07-05T14:26:31.600Z",
      "updated_at": "2024-07-05T14:27:02.905Z",
      "object": "campaign_template"
    }
  ],
  "total": 14,
  "has_more": true
}