curl --request GET \
  --url 'https://backend.testeswaffle.org/referrals/activate?subscriptionId=indicado@exemplo.com'

{
  "success": true,
  "data": {
    "referral_id": "ref_987654321",
    "status": "active",
    "activated_at": "2024-01-15T14:30:00Z"
  }
}