Please provide a command to list the count of voucher(s) of a user

[nevart]

Please implement a command like:

app:voucher:create -- Create voucher for a specific user

i.e.

app:voucher:list -- List count of voucher(s) for a specific user

Use case: this allows to list the count of voucher(s) of a user, to do a sanity check before assigning new voucher(s).