interop: Ingress Filtering for Interop Enabled Mempool

[axelKingsley]

What

Creates components for filtering Transactions out of the mempool if they create invalid Executing Messages

Ingress Filters

In the txpool package, IngressFilters take a Tx and return a boolean if the tx is acceptable to move forward.

InteropFilter

An implementation of an Ingress Filter, this takes and uses two functions to collect logs for the given Tx and ask the Supervisor about the validity of them.

txpool

TXPools now hold a slice of Ingress Filters. When calling Add, each transaction is passed through each filter, and if a filter would drop the transaction it is noted, and returned as a new FilteredOut error.

Ethereum Backend

The backend now features a function to get logs by simulating a transaction, called SimLogs. When creating a new backend, if Interop is enabled, the TX Pool is given an InteropFilter which is attached to the SimLogs and CheckMessages functions.

TODO:

• No testing is done for SimLogs. CC @protolambda , I actually don't know how to test this function since it uses so many core components. I based this function on code in the Tracing components. EDIT: the best way will probably be to develop and E2E test in the monorepo which demonstrates it
• The txpool or the filter might want to remember transaction hashes and cache the results to prevent a dos against it.

[protolambda]

Rebased this, squashed the commits, moved some interop logic into its own file + documented it in the fork.yaml.
And made some changes:

• The log-simulation now denies txs more eagerly. Safety over liveness of a tx. A user can resubmit if necessary. There are still ways to bypass the ingress filter, but we'll working on hardening that in later PRs.
• The log-simulation now uses the block attributes, like the block fee-recipient, to better match the actual environment of tx execution. And uses the block gas limit, rather than the tx gas limit, to not go too high with gas allowance.
• The tx-pool now has a filter-context, which is closed on tx-pool shutdown, to cancel any ongoing filter work. And the check-messsages RPC call has a timeout now.