Audit helper correction

The first final peer-report and neighbour-screen runs encountered KeyError: 'key'
because their file glob included a newly generated noncandidate JSON file in
the drafts directory. The helpers were narrowed to the four authored strand
filename prefixes and keyed candidate records. Both reruns completed.

No candidate definition, retained source, baseline record or review decision
was altered by this helper correction. This was a report-generation error,
not a failed artifact integrity or source-pin check.
