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.
