@illostack/store is framework-agnostic, so you can use it with any JavaScript framework. Simply install and use it just like the React version but without the useStore and useStoreEffect hooks.
No, @illostack/react-store is specifically designed for React. If you need a framework-agnostic store, use @illostack/store.
You can use @testing-library/react along with Jest or Vitest for testing. Ensure that you render your components, and use the getByText or queryByText to verify the state.
For larger applications, you can split your stores and use multiple useStore hooks to access different parts of the state. You can also consider using state selectors to reduce unnecessary re-renders.