Move rpc compat into OpEthApi

[mattsse]

Describe the feature

for #16451 we should do the same for OpEthapi as we did for ethapi:

reth/crates/rpc/rpc/src/eth/core.rs

Lines 63 to 68 in c36b543

	pub struct EthApi<Provider: BlockReader, Pool, Network, EvmConfig> {
	/// All nested fields bundled together.
	#[deref]
	pub(super) inner: Arc<EthApiInner<Provider, Pool, Network, EvmConfig>>,
	/// Transaction RPC response builder.
	pub tx_resp_builder: EthTxBuilder,

reth/crates/rpc/rpc/src/eth/core.rs

Lines 163 to 165 in c36b543

	fn tx_resp_builder(&self) -> &Self::TransactionCompat {
	&self.tx_resp_builder
	}

instead of for OpEthapi

reth/crates/optimism/rpc/src/eth/mod.rs

Lines 112 to 114 in c36b543

	fn tx_resp_builder(&self) -> &Self::TransactionCompat {
	self
	}

reth/crates/optimism/rpc/src/eth/transaction.rs

Line 89 in c36b543

impl<N> TransactionCompat<OpTransactionSigned> for OpEthApi<N>

this way we can decouple the rpc response and the txtype:

reth/crates/optimism/rpc/src/eth/transaction.rs

Line 99 in c36b543

tx: Recovered<OpTransactionSigned>,

and make this a configurable on OpEthapi itself

Additional context

No response