React Starter
This example shows a React application that renders a static SVG smiley face with two circles for eyes and a large yellow circle for the face. It uses React 16.13.1 with functional components and hooks, specifically `useState` and `useEffect` imported but not utilized. The component returns a fragment containing a message div and an SVG canvas, with circles positioned using fixed `cx`, `cy`, and `r` attributes. D3 v6 is loaded but not used in the rendering. The app mounts to the `#root` element via `ReactDOM.render`.