- shouldAcceptFix: accept when first fix, >=10 m moved, or >=5 s elapsed
(whichever first) — the pure accept rule over haversineM
- createGuidanceWatch(geo, onFix): high-accuracy watchPosition
(maximumAge: 0), six-field Fix normalization (null accuracy/heading,
source webview), rejected fixes die in the wrapper, idempotent stop()
clearing the watcher id (T-06-05b's privacy-minimal trip end)
- replay suite T1-T3 + R12b: truth table, recorded-options structural
gate, feed-only-accepted proof, stop idempotence, module purity scan