React 18 let's make ref.currant to be reactive value

Let's add this hook as part of the core. Since this is a common need, many people often ask the question "Why does useEffect not sense ref.current changes?" ```js // approximate implementation const useReactiveRef = (defaultValue) => { const [current, ref] = useState(defaultValue) ref.current = current return ref } ``` Usage example: ```js const Component = () => { const ref = React.useReactiveRef() useEffect(() => { // ref.current now is reactive console.log(ref.current) }, [ref.current]) return <div ref={ref}></div> } ```