P2 tests now force conditions instead of observing them:
FC3: Real WAL scan verified directly — StreamWALEntries transfers
real entries from disk (head=5, transferred=5). Engine planning also
verified (ZeroGap in V1 interim documented).
FC4: ForceFlush advances checkpoint/tail to 20. Replica at 0 is
below tail → NeedsRebuild with proof: "gap_beyond_retention: need
LSN 1 but tail=20". No early return.
FC5: ForceFlush advances checkpoint to 10. Assertive:
- replica at checkpoint=10 → ZeroGap (V1 interim)
- replica at 0 → NeedsRebuild (below tail, not CatchUp)
FC1/FC2: Labeled as integrated engine/storage (control simulated).
New: BlockVol.ForceFlush() — triggers synchronous flusher cycle for
test use. Advances checkpoint + WAL tail deterministically.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
cd4b91033f