refactor(storage): resolve staged dead code in store module (#730)
Drop the store module's blanket #![allow(dead_code)] and resolve every
unit it was masking, instead of keeping them staged:
- write_persistent_key_only_index: the keys-only writer wrapper only had
test callers; the in-process rebuild flow already exists and uses the
_with_metadata variant (prepare -> rebuild, triggered lazily from the
opt-in listing path). Tests call _with_metadata directly now.
- ListIndexLifecycle::recover_after_restart / mark_corrupt: production
derives index health per request from the persisted artifacts (index
file + namespace mutation journal), and restart recovery already lives
in load_persistent_key_only_index's journal restore. The persisted-
lifecycle design these transitions served was superseded, and Corrupt
had no detector, so the never-constructed Corrupt state/reason
variants go with them.
- record_list_objects_index_opt_in_fallback (+ helpers): superseded by
the inline per-site fallback recording in the opt-in listing path; the
recorder recomputed health with a hardcoded None provider, so it could
only ever report a disabled-based reason.
- Provider-contract traits (Generation/Page/PageIterator/KeyLookup):
provider dispatch went the ListObjectsIndexProviderKind enum route;
only ListMetadataIndexHealth is live (dyn in source-mode selection)
and stays, minus its unused is_healthy default.
- Delete the unused list_quorum_from_env/RUSTFS_API_LIST_QUORUM pair,
fold should_resume_local_decommission and
should_auto_start_rebalance_after_recovered_meta into their surviving
primitives, drop get_disk_via_endpoint, and cfg(test) the remaining
test-only conveniences.
cxymds