In metadata chunks mode the server sends log file refs in responses of their
own, and the client can only read them once it knows the run of refs is over.
That was inferred solely from the arrival of a normal event, so refs still
pending when the stream ended were dropped: the subscription returned no
events and no error.
A follower never noticed, because it runs forever and a live event always
arrives to close the run. A bounded subscription — StopTsNs set, range already
in the past — can receive nothing but refs and then EOF, and silently reports
that nothing happened. For anything auditing a path that is the worst possible
answer, since an empty result is indistinguishable from a quiet period.
Drain on EOF as well as at the transition point.