established/related keeps the in-flight session alive across the swap, so the
prior 'next task runs' confirm always passed even if new connections were
bricked — the rollback was theater. reset_connection + wait_for_connection now
force a fresh handshake through the new ruleset; failure aborts the play and the
armed timer reverts. (meta: reset_connection ignores 'when' — benign extra
reconnect on no-op runs; verified idempotent in molecule.)