curl --request GET \
  --url http://localhost:8080/cabinet/referral

{
  "referral_code": "<string>",
  "referral_link": "<string>",
  "total_referrals": 123,
  "active_referrals": 123,
  "total_earnings_kopeks": 123,
  "total_earnings_rubles": 123,
  "commission_percent": 123
}