curl --request POST \
  --url https://api.lyceum.technology/api/v2/external/voucher/validate \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "email": "jsmith@example.com",
  "code": "<string>"
}
'

{
  "valid": true,
  "voucher_id": "<string>",
  "voucher_amount": 123,
  "error": "<string>"
}