Open the stale-refresh-time window on any resolver failure

Open the stale-refresh-time window on any resolver failure

The TCP-fallback fix in the previous commits means a query that would
previously have timed out on UDP now actually escalates to TCP, and a
TCP-side failure surfaces a non-ISC_R_TIMEDOUT result code to
query_usestale().  The trigger for DNS_DBFIND_STALESTART was previously
narrowed to ISC_R_TIMEDOUT, so the stale-refresh-time window stopped
opening for those clients.

Broaden the condition to any failure that has already cleared the
upstream DUPLICATE/DROP filtering in query_usestale() — the spirit of
the window is "the resolver tried and could not get a fresh answer",
not "the resolver timed out specifically".

Co-authored-by: Evan Hunt <each@isc.org>
Assisted-by: Claude:claude-opus-4-7