repairIndex() now returns a RepairReport: one row per repair family
(orphaned containers, count rollups, VFS containment, metadata corruption,
write quarantine, each provider's invariant pass, degraded-read state) with
checked / healed counts and an explicit skip reason for anything not run —
no silent rows. A summary line narrates families checked and heals applied.
This is the receipts half of the graph-trust program's ask: a repair that
cannot show its work per store is a repair nobody can audit. Pinned: a
healthy store yields a complete zero-heal receipt with every family
accounted; a manufactured pre-8.3.1 ghost container appears in the receipt
as a counted heal. Additive: void-callers are unaffected.
