The raw input/result bytes of import/export conversion jobs were kept
forever; a deleted classified page could live on inside its last export.
A new daily conversion-payload-prune job nulls both once a finished
(succeeded or failed) job passes conversion.payloadRetentionDays
(instance setting, default 30) — the row survives for status/audit.
PENDING and RUNNING rows keep their payload, so the worker's stale-lock
recovery path is untouched; a hand-requeued pruned job fails finally
via conversionInputOf instead of crashing the worker.
The input column becomes nullable; the migration backfills by clearing
payloads of jobs already finished longer ago than the default period
(recent results stay downloadable until they age out).
Job-count fence in system.spec: 7 -> 8 (new scheduler registration).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0168Ph5uBmHm8X28CSVpbpnJ
