Two rules the first mutation pass found undefended in every runtime: a new
Connect on a session that had a peer clears the old peer's received window (a
restarted server's sequences overlap the old ones), and ending a session
abandons its pending Connect. The cultmesh-py server test now counts the
server's own data packets by sequence, so a peer replaced on a retransmitted
Connect is seen, and asserts a restarted client inherits no subscription.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>