Verify l2 withdrawals root in live sync

[emhane]

Describe the feature

Verify isthmus withdrawals root with consensus rules implemented in #14308 either before, or optimistically after, this statement.

reth/crates/engine/tree/src/tree/mod.rs

Line 2551 in c9a348d

let hashed_state = self.provider.hashed_post_state(&output.state);

Pros of doing before is early bail if l2 withdrawals root doesn't verify and skip hashing all state updates (just the state updates for the predeploy account, if any).

To do this we either need to surface the EngineApiTreeHandler to sdk level, or some hack with adding a trait method FullConsensus::validate_block_post_execution_live_sync_only

wdyt @mattsse @klkvr

Additional context

No response

[mattsse]

To do this we either need to surface the EngineApiTreeHandler to sdk level

this is planned but this requires a lot of work.

for this feature I think we can get away with integrating this into the PayloadValidator instead. we should treat this validation step similar to state root, and check outside of the consensus traits (maybe we should consider integrating this there eventually).

but I believe an easier integration would be in the payloadvalidator for now
and replicate

reth/crates/optimism/payload/src/builder.rs

Lines 403 to 418 in c5df8fb

	let hashed_storage_updates =
	state.bundle_state.state().get(&ADDRESS_L2_TO_L1_MESSAGE_PASSER).map(|account| {
	// block contained withdrawals transactions, use predeploy storage updates from
	// execution
	HashedStorage::from_plain_storage(
	account.status,
	account.storage.iter().map(|(slot, value)| (slot, &value.present_value)),
	)
	});
	// withdrawals root field in block header is used for storage root of L2 predeploy
	// `l2tol1-message-passer`
	Some(state.database.as_ref().storage_root(
	ADDRESS_L2_TO_L1_MESSAGE_PASSER,
	hashed_storage_updates.unwrap_or_default(),
	)?)

the state root stuff is super messy rn (working on it).

[emhane]

this new method for verifying against hashed storage fits better into FullConsensus trait, no? alongside validate_block_post_execution

reth/crates/consensus/consensus/src/lib.rs

Lines 30 to 45 in faa55d9

	/// [`Consensus`] implementation which knows full node primitives and is able to validation block's
	/// execution outcome.
	#[auto_impl::auto_impl(&, Arc)]
	pub trait FullConsensus<N: NodePrimitives>: AsConsensus<N::Block> {
	/// Validate a block considering world state, i.e. things that can not be checked before
	/// execution.
	///
	/// See the Yellow Paper sections 4.3.2 "Holistic Validity".
	///
	/// Note: validating blocks does not include other validations of the Consensus
	fn validate_block_post_execution(
	&self,
	block: &RecoveredBlock<N::Block>,
	result: &BlockExecutionResult<N::Receipt>,
	) -> Result<(), ConsensusError>;
	}