PR #20 landed the spec-conformant transport on ethp2p-rs main (squash-merged
as d852f23). Move the pin off the pre-merge branch commit (3d23411) to that
main commit, which additionally brings in the hardening added after the Slice-7
bump: reconstruct-reset, per-peer bounded queues with backpressure, opt-in
peer-id pinning, and — importantly — the fix for a load-dependent livelock
where a backpressured chunk send spun drain_session without yielding.

Pinning to a commit on main (rather than a branch that may be deleted) also
gives the git dependency stable provenance. No adapter changes: the new
transport APIs are additive, so bind/connect/Net::send/events are unchanged.
The in-crate round-trip test and the default feature-off build both pass.