Deliverables 3 & 4: per-item blast radius + soak signals, and the before/after
worst-case synchronous blocking for every hot path touched (prune, sweeps, OTA,
register, telemetry). Ends with the A<->B interlock note (ship together).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>