Use B256 instead of U256 in access list keys

[DaniPopes]

Both Reth and Foundry use B256 and have to use utilities to convert to U256:

• https://github.com/foundry-rs/foundry/blob/fdaed8603fc330cbc94c936f15594bccdc381225/crates/anvil/core/src/eth/utils.rs#L19
• https://github.com/paradigmxyz/reth/blob/56a3548915ec1d369ddf3067911fb730939e63f8/crates/primitives/src/transaction/access_list.rs#L47C1-L47C1

I think the bigger problem here is that Revm uses U256 for all storage slot key and values, which has a different memory layout than B256.

[rakita]

U256 is used as the stack in revm is U256 and most of the instructions are done easier on u256 so the storage keys are all in u256.

There is a possible discussion if we would like for storage keys to be B256 types, then we do transition from stack U256 to B256 when SLOT/STORE are used but I feel that there will be slight downsides than the benefits.

I think the very beneficial thing for this will be Generics over Transaction: #916
would make this a lot easier to do.

[rakita]

Will close this in favor of #916