v0.18.0

[0.18.0] - 2026-09-03

Added

• Embedded 0-RTT parity and the prehandshake buffer (Experimental;
  rpc.transport.quic). EmbeddedSessionOptions gains early_data and
  early_dispatch, and the seat derives the engines' replay hold from them
  exactly like the owned loop's fromServer — closing a parity gap where
  the seat hardcoded the hold off, which would have let a replayed 0-RTT
  first flight execute RPC frames on a host listener accepting early data
  without anti-replay. rpc.transport.quic.prehandshake is the host-side
  companion: a bounded, arrival-ordered buffer for stream events that
  arrive before the handshake names the protocol (resumed dials), replayed
  into the winning seat at handshake time. The embedded test suite gained
  the resumed-0-RTT e2e over a foreign host — early frame delivered exactly
  once, never dispatched before the handshake completes, hold armed from
  the listener posture.