Avoid cloning block in EngineApiTreeHandler::insert_block

[nekomoto911]

Describe the feature

In EngineApiTreeHandler::insert_block, it is desirable to include block in the error and return it when EngineApiTreeHandler::insert_block_inner is unsuccessful. However, insert_block_inner needs to take ownership of block, so a clone of block is made. Cloning SealedBlockWithSenders involves deep copying of transactions, receipts, etc., which is a costly operation. Since insert_block_inner typically returns OK, always performing a costly operation for a rare exceptional case is not considered best practice.

EngineApiTreeHandler::insert_block_inner appears to be called only by EngineApiTreeHandler::insert_block. So could we let insert_block_inner directly return InsertBlockErrorTwo in case of an exception to avoid cloning the block?

If you find this suggestion reasonable, please assign this issue to me. I am very expected to contribute to the project!

Additional context

No response

[nekomoto911]

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

Lines 2163 to 2169 in c697543

	fn insert_block(
	&mut self,
	block: SealedBlockWithSenders<N::Block>,
	) -> Result<InsertPayloadOk2, InsertBlockErrorTwo<N::Block>> {
	self.insert_block_inner(block.clone())
	.map_err(|kind| InsertBlockErrorTwo::new(block.block, kind))
	}

[mattsse]

yeah this has been on my backlog for a while,

this def needs improvement, and should be fixed by simplifying the error handling here, either by stripping the block context from InsertBlockErrorTwo or removing the map_err