onQuit

When someone quits, update their entry with the current timestamp iff they already have an entry.

QUIT events don't carry a channel. Users bleed into the seen users database from guest channels by quitting unless we somehow limit it to only accept quits from those in homes. Users in home channels should always have an entry, provided that RPL_NAMREPLY lists were given when joining one, which seems to (largely?) be the case.

Do nothing if an entry was not found.

version(WithSeenPlugin)
private
void
onQuit