curl -X POST http://localhost:13579/api/license/validate \
  -H "Content-Type: application/json" \
  -H "X-Machine-ID: ABCDEF123456" \
  -d '{
    "payload": "eyJtYWNoaW5lX2lkIjoiQUJDREVGMTIzNDU2IiwiZXhwaXJ5IjoiMjAyNi0xMi0zMSIsImZlYXR1cmVzIjpbImdwdSIsIm9jciJdfQ==",
    "signature": "MEQCIGAUy3lw7r3hJ/WxNs6ifRp+2SwuDO/2xBm7TjPdvoB6AiALASU3VPnZGxlHP8UMbLwPP1dxulPJ2cknduQaAREjbA=="
  }'