`eth` message type metrics

[Rjected]

Describe the feature

Even if we don't handle a certain type of request, it would be interesting to see what kinds of requests we are receiving, and in what proportion (GetReceipts, GetBlockHeaders, ...). We should add metrics for this.

This would involve introducing a new metrics type with counts for each type of eth message, and then increment the counts here: https://github.com/paradigmxyz/reth/blob/081796b138fd00a6d0af2ad463123fdbe04765ab/crates/net/network/src/eth_requests.rs#L236-L258

Additional context

No response