Disk-replacement heal previously repaired only the latest version of each
object and never enumerated objects whose latest version is a delete marker,
so old versions were left unrepaired on a replaced drive.
Switch heal enumeration from list_objects_v2 (latest-only) to
list_object_versions (every version incl. delete markers), thread the concrete
version_id into the existing per-version heal_object, and make resume
cursor-based instead of positional: an opaque (marker, version_marker) paging
token persisted in ResumeState, a length-prefixed injective per-version dedup
key, schema_version bumps (v2) migrated independently in each of the two
persisted files, and a retry that resets both managers together (fixing a
latent rescan-skips-everything defect). Adds a real-disk-wipe e2e regression
suite proving old versions and delete-marker-latest objects are physically
restored.
Fixesrustfs/backlog#918Fixesrustfs/backlog#919Closesrustfs/backlog#854
