curl -X POST 'https://api.wovepay.com/v1/billings/refund' \
  -H 'X-API-Key: wp_live_SUA_CHAVE' \
  -H 'Content-Type: application/json' \
  -d '{ "id": "clx_billing", "amount": 50, "reason": "Devolução parcial" }'

{
  "success": true,
  "message": "Estorno solicitado com sucesso",
  "data": {
    "id": "clx_billing",
    "status": "REFUNDED",
    "statusLabel": "Estornado",
    "method": "PIX",
    "amount": 79.9,
    "netAmount": 76.91,
    "feeAmount": 2.99,
    "description": "Pedido 123",
    "externalId": "pay_abc123",
    "externalReference": "pedido-123",
    "refundExternalId": "ref_xyz",
    "createdAt": "2026-05-30T10:00:00.000Z",
    "customer": {
      "id": "clx_customer",
      "name": "Cliente Exemplo",
      "taxId": "12345678909"
    }
  },
  "requestId": "req_abc123"
}