v1.21.1

[1.21.1] — 2026-10-11

heavy-review: verification may be merged. Rounds and severity rules are unchanged; by default one verifier subagent checks all of a round's findings and gives a verdict for each, splitting into a few parallel groups only when there are too many for one agent. Review-gate notice, the four review skills, the verification prompt and docs updated; the gate already counts N=1.