curl -X POST http://localhost:3000/api/pdf/reporteB \
  -H "Content-Type: application/json" \
  -d '{
        "constantes": [
          {"tipo": "Frecuencia cardíaca", "valor": "78 bpm", "fecha": "2025-10-22"},
          {"tipo": "Temperatura", "valor": "36.6 °C", "fecha": "2025-10-22"}
        ]
      }' \
  --output reporteB.pdf