V004 seeds corpus_revision=0, V009 migration bumps to 1 (spec §5.2 —
LRU cache invalidation). Test previously asserted fresh store = 0;
now reads post-migration baseline dynamically and verifies that the
ingest commit increments past it.
Spec: docs/superpowers/specs/2026-05-28-v0.20.x-korean-morphological-tokenizer-spec.md §5.2
Plan: docs/superpowers/plans/2026-05-28-v0.20.x-korean-morphological-tokenizer-plan.md (S3 follow-up)