curl --request GET \
  --url http://localhost:8080/promo-codes/{promocode_id}

{
  "id": 123,
  "code": "<string>",
  "type": "balance",
  "balance_bonus_kopeks": 123,
  "balance_bonus_rubles": 123,
  "subscription_days": 123,
  "max_uses": 123,
  "current_uses": 123,
  "uses_left": 123,
  "is_active": true,
  "is_valid": true,
  "valid_from": "2023-11-07T05:31:56Z",
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z",
  "total_uses": 123,
  "today_uses": 123,
  "valid_until": "2023-11-07T05:31:56Z",
  "created_by": 123,
  "recent_uses": [
    {
      "id": 123,
      "user_id": 123,
      "used_at": "2023-11-07T05:31:56Z",
      "user_username": "<string>",
      "user_full_name": "<string>",
      "user_telegram_id": 123
    }
  ]
}