curl: 27: IMAP custom FETCH listing classification skips literal boundaries, enabling response desynchronization

Summary iscustomfetchlistingmatch in lib/imap.c classifies any custom FETCH whose sequence set contains : or , as a "listing." For that classification, imapstatelistsearchresp skips literal detection entirely. The ping-pong line parser then scans the server-declared literal body as IMAP protocol...