curl --request GET \
  --url https://{operatorDomain}/v1/admin/finance/vouchers \
  --header 'Authorization: Bearer <token>'

{
  "data": [
    {
      "id": "vch_01HZX...",
      "code": "WELCOME50",
      "currency": "EUR",
      "valueCents": 5000,
      "status": "active",
      "remainingCents": 5000,
      "expiresAt": "2023-11-07T05:31:56Z"
    }
  ]
}