- lib/store.ts: createStore<T> — one observable-value primitive (get/set/subscribe/use)
replacing the hand-rolled listeners/subscribe/emit triad several modules each had.
- lib/storage.ts: LS key registry (every siftlode.* key in one place), readMerged/
readJSON/writeJSON (the try/JSON.parse/merge/catch done once), and usePersistedState
(the reactive persisted-string hook, generalizing usePersistedTab).
