op-chain-ops: Fix flaky TestCode

If getting an empty code value in the state DB, geth returns `nil`,
not an empty array. This is funcationally equivalent if you are checking
the length, but not the same if you expect to get the same object out
that you put in. This now checks for this special case & prevents
the test from flaking.

This can be tested by running `go test ./state -count=10 -run=TestCode` in
the op-chain-ops folder. Without this change the test will fail, with this
change it will now pass.

contracts-bedrock: erc721 bridge single impl

Update the ERC721 bridge so that a single implementation
can be used across many different chains.

Still need to double check the storage layout before this
is good, but the tests are passing.

Also need to update all the code that touches the go bindings.

feat(indexer): Index CrossDomainMessenger messages

feat(indexer): Index OptimismPortal & L2ToL1MP Txs

chore: Clean up op-e2e Dispute Game Helpers

contracts-bedrock: single implementation L1StandardBridge

op-e2e: Use helper to send deposit tx in TestMixedDepositValidity

Helper avoid flakiness by padding the gas limit for the L1 tx.

feat(ctb): `MIPS` constructor