feat: return a human readable denomination for IBC vouchers when querying bank balances

[crodriguezvega]

Summary

Return a human readable denomination for IBC vouchers when querying bank balances.

Problem Definition

Currently when the account balance of an address is queried and it has IBC vouchers, then the denomination for those vouchers will be the hashed IBC denom, which is not very human readable friendly. In order to get a human readable denom, a second query needs to be performed to translate the hashed IBC denom to the full trace path.

Issue #1480 was opened in ibc-go to address this issue. A potential solution was explored in the issue to expose in ibc-go a new query endpoint that would return the same result as the regular balances query, but incorporating an extra field with the full trace path trace in case the balance of the account included IBC vouchers. This solution is not idea, though, since clients would need to switch to this new query endpoint.

Proposal

In ibc-go we could use x/bank's Metadata to set metadata for an IBC voucher when it is minted for the first time. If the metadata is present for an IBC voucher, the query for bank balances could make use of the metadata to display a human readable denom (this translation could be done based on the value of a flag). If metadata is not present or the flag is not enabled, then the query for bank balances would return the regular hashed IBC denom.