-- pg_turbovec 2.8.0 -> 2.8.1
-- Documentation-only: corrects v2.8.0's cross-scale comparisons (the 1M corpus
-- is a different model than the 250k one, since the older dataset is now
-- gated), records a trap in the contention-filtering verification method, and
-- restores the ground-truth-fix section lost to an earlier rewrite.
-- Binary byte-identical to 2.8.0. No wire change (v8), no REINDEX.
-- Intentionally empty but MUST exist so ALTER EXTENSION ... UPDATE succeeds.