curl --request GET \
  --url https://api.service.getjusto.com/v3/royalty/client-loyalty-balance

{
  "success": true,
  "data": {
    "clientId": "rty-cli-001",
    "email": "[email protected]",
    "justoUserId": "u-001",
    "balance": 150,
    "websiteId": "w-001",
    "lastUpdated": "2025-10-14T14:16:11.000Z"
  }
}