DirectoryMessagePackBackingStore loses HydrationFilter, FlushStageProbe,
ReadStageProbe and their stage constants, ReadPersistedGeneration,
PullSelected, and every legacy path: the v2 directory-indexed and v3
immutable-pages formats, v1 inline records and split pages, the index
upgrade on flush, and the legacy page paths. CacheBackingStore.PullSelected
and CultPersistedRecordMetadata go with them.
A missing manifest is an empty store. An existing manifest whose
FormatVersion is not cultcache.store.v4.directory-content-addressed-pages
throws "Directory store {path} is {format}; only {v4} is readable." A clean
flush writes nothing, since there is no legacy index left to upgrade.
Tests deleted with the surface they injected through: the v1 missing-catalog
load, pages-before-manifest, fault-before-manifest (4 cases), same-timestamp
page, mutation-during-flush and reader-lease tests. The orphan-page test now
checks through a fresh store pull instead of ReadPersistedGeneration.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
900e148d8a