curl --request POST \
  --url http://localhost:8080/miniapp/subscription/trial \
  --header 'Content-Type: application/json' \
  --data '
{
  "initData": "<string>"
}
'

{
  "success": true,
  "message": "<string>",
  "subscriptionId": 123,
  "trialStatus": "<string>",
  "trialDurationDays": 123,
  "chargedAmountKopeks": 123,
  "chargedAmountLabel": "<string>",
  "balanceKopeks": 123,
  "balanceLabel": "<string>"
}