* fix 11388
* fix(volume): scrub validates local deletion tombstones
TombstoneFileSize (-1) is an .idx-only sentinel; the physical record it
points at carries a zero-sized body. Normalize deleted index sizes to 0
via onDiskSize before computing disk usage and calling ReadData, so
corrupted or truncated tombstone records are detected instead of
skipped. Offset-zero entries (remote logical deletes, no .dat record)
remain skipped, and the physical needle id is checked against the index
key. Mirror the behavior in the Rust volume server.
* fix(volume): scrub preserves physical size of deleted non-tombstone entries
Size.Raw()/raw() already encodes the index-to-disk mapping: tombstone
(-1) -> 0, other negative sizes -> their absolute value (the offset then
points at the original record, per the ReadDeleted path). Use it instead
of mapping every deleted size to 0.
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Co-authored-by: Chris Lu <chris.lu@gmail.com>
cd1e738422