ShouldTellPeerOfCloseQUIC: twenty clients connect to a listener whose
idle timeout is 20 s and are destroyed in turn; for each, the server
side's RecieveDatagramSync, which throws once the peer has closed the
connection, must return within 2 s. Before the fix the first one never
did, since ~ClientQUIC closed its handle before msquic had sent the
CONNECTION_CLOSE frame; the loop stops at the first miss, as every
later connection would wait out its 2 s too.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
