backfill_event_shape.py skipped rows whose .h5 produced no shape and left
the previously stored value in place. A stale shape outlives the decode
it came from and silently feeds the false-trigger detector.
Found while re-running the backfill after the histogram codec fix: 493
rows in the prod snapshot were carrying shape metrics that no longer
matched their .h5 — e.g. BE17353/S353LDOK.XZ0H held crest_factor from a
223-sample decode while its .h5 holds a single interval. These predate
today's work (present in the pre-32000 snapshot), so this is pre-existing
behaviour rather than fallout from the codec fixes.
Now NULLs shape_crest_factor / shape_near_peak_count / shape_sample_count
/ shape_axis in that case and reports a `cleared_stale` count. Verified
on the snapshot: 493 cleared, 0 stale rows remaining, 11570 rows matching
their .h5 exactly.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HgTe8CamXAHcAmaQ6QNcog
serversdownandClaude Opus 5