Installs globalThis.__uatu__ with extract, always, actions,
weighted, tap, inputText, and stub taps/swipes. Load runs the
bundled spec, then pulls properties + actions out of globalThis.
PushSnapshot rebuilds state.snapshots and refreshes every
extractor handle's current/previous in registration order so
chained extractors observe up-to-date values.
Properties are wired through internal/ltl as Always(Thunk(...)),
so verdicts latch to violated as soon as a predicate returns
false. NextAction resolves actions/weighted recursively with a
seedable rand source for reproducible runs.
pj