PVAutoExpanding fired at >80% used (info severity), but pvc-autoresizer's
threshold is 10% free (= 90% used) — the alert always fired ~10 points
before any action would have been taken, and there was nothing for an
operator to do during that window either. It was a "heads up" that
didn't surface a problem.
Real failure modes are already covered:
* PVFillingUp (critical, >95% for 10m) — autoresizer didn't keep up
* PVPredictedFull (warning, predict_linear 24h) — trend toward exhaustion
Sharpened PVFillingUp's annotation to spell out the likely causes
(storage_limit reached, expansion failing, or missing autoresizer
annotations) so the responder doesn't have to recall the runbook.
cd13b9d062