React 19 Source Desk - an independent helper that moves one React file to createRoot, ref props and default params

Move one React source file to React 19. Free in your browser: ReactDOM.render rewritten to createRoot(...).render and ReactDOM.hydrate to hydrateRoot with the react-dom/client import, an untyped forwardRef to a function component that takes ref as a prop, defaultProps on a function component to default parameters (class components keep static defaultProps), useRef() to useRef(null), the React 19 note above propTypes - and findDOMNode, unmountComponentAtNode, typed forwardRef, legacy context, string refs and an unused React import flagged, plus the checklist, the steps and CSVs. Metered runs write the review (each finding decided, what a scan cannot see, the order) and the whole React 19 file, which the page re-scans. It re-scans the files it writes; it does not compile or run them. An independent tool, not affiliated with or endorsed by Meta or the React team. Built on the SkillSafe skill @github/react19-source-patterns, from github/awesome-copilot (MIT).