573e505a4b
Six tasks: StallClock plus the chat loop, then embedding, ocr, the config comments, the full-suite regression with doc sync, and independent verification. Codex review raised four points, all confirmed and folded in: a stale line reference in the fidelity section, explicit cancellation acceptance for T2/T3 (the new attempting() wrapper now wraps their existing cancel paths), a telemetry-boundary test pinning the design's claim that telemetry jitter must not feed the stall verdict, and concrete test construction for the embedding/ocr regressions.