Transfering WNAM to namada should burn the same amount

[Fraccaman]

No description provided.

[sug0]

For this issue and #56, could we do something like the gravity bridge does,

https://github.com/Gravity-Bridge/Gravity-Bridge/blob/8ba6deb81373d9d3b702d22d20bca028f74dc2ed/solidity/contracts/Gravity.sol#L590-L609

https://github.com/Gravity-Bridge/Gravity-Bridge/blob/8ba6deb81373d9d3b702d22d20bca028f74dc2ed/solidity/contracts/CosmosToken.sol#L33

where one contract owns the maximum representable supply of the native token?

In our case, the Vault could mint MAX_UINT worth of wNAM. On transfers to Ethereum, if the vault detected the transferred asset was wNAM, it would release wNAM from its internal pool, since it owns the entire representable supply. Transferring to Namada, we could "burn" tokens by transferring them back to the Vault.

Capping wNAM could be done Namada-side. See anoma/namada#1722

[Fraccaman]

Agree, easier and faster solution.