lazyLoadCounts() read the `__sparse_index__noun` blob, but the sparse-index
WRITE path was removed in 7.20.0 — new workspaces persist the 'noun' field
ONLY to the column store. So on close()+reopen the sparse load found nothing
and left every per-type count at 0: counts.byType / byTypeEnum / topTypes /
allNounTypeCounts all read empty, while find() / getNounCount() (different
sources) stayed correct.
Rehydrate from the column store's 'noun' field instead. Its per-value
cardinality matches the warm updateTypeFieldAffinity counts exactly because
both are driven from the same addToIndex field set, in lockstep, with no
visibility gate on either — so syncTypeCountsToFixed (called right after in
init) reproduces the warm fixed-array values precisely. Legacy chunked sparse
index kept as a fallback for pre-7.20.0 workspaces.
Ground-truth verified: 12 Person + 5 Document → cold reopen now reports
person:12 / document:5 (was 0), topTypes [person, document, collection].
Tests: un-skipped the intentionally-failing phase1c "warm cache on init"
reopen test and strengthened it to exact persisted counts; added a warm==cold
element-for-element equality test. 1464 unit + count-sync/multi-process/
clear-persistence integration green.