Ethermint uses Tendermint Hashes

[jbowen93]

Currently Ethermint uses Tendermint hashes for blocks. This is problematic because when Optimism retrieves a block it validates its header https://github.com/celestiaorg/optimism/blob/develop/op-node/l1/types.go#L113

if computed := header.header.Hash(); computed != info.hash

These hashes do not match

[jbowen93]

I'm going to attempt to create a middleware layer that converts Ethereum hashes to Tendermint hashes prior to passing retrieve call to Optimint/Tendermint.

[jbowen93]

The best way to move forward here is to include both the tendermint hash and the ethereum hash on each block. Then we can create an index between the two.