feat: Support sending raw capability messages

[stevencartavia]

should close #13005

[stevencartavia]

should I update self.bytecode_hash.is_none_or(|hash| hash == KECCAK_EMPTY)? I don't see the relationship with the changes

[mattsse]

great start

would be nice to get a test for this as well

see

reth/crates/net/eth-wire/src/ethstream.rs

Line 611 in b09c345

async fn ethstream_over_p2p() {

[mattsse]

what we need to do here instead is encode the entire msg together with the id.

see:

reth/crates/net/eth-wire-types/src/message.rs

Lines 109 to 113 in b09c345

	/// Encodes the protocol message into bytes. The message type is encoded as a single byte and
	/// prepended to the message.
	fn encode(&self, out: &mut dyn BufMut) {
	self.message_type.encode(out);
	self.message.encode(out);

[mattsse]

very nice!