Resolving tx inputs in transactions in mockchain

[koslambrou]

As a user of the Mockchain in testing, I want to be able to resolve the transaction inputs of some Tx.

By resolve, I mean going from C.TxIn to C.TxOut era. This is typically done by a chain-indexer, but the Mockchain should be capable of doing so. Currently, we are able to resolve C.TxIn, but only if they are unspent.

Possible solution

Similar to mscDatums, should we separately index the transaction outputs instead of using mcsPoolState?

For example, we can add another field in MockchainState such as Map C.TxIn (C.TxOut ERA)? Then, we can also use that to resolve the TxIn in utxoByTxIn function of MonadBlockchain.