Smiley face part 1
This example shows a simple smiley face drawn as a static SVG graphic, with a yellow circular head, two black eyes, and the expectation of a mouth to be added in a later part. The React component defines the SVG canvas using fixed dimensions and centers the shapes with computed coordinates. The code uses React 17, ReactDOM, and the `arc` function from D3 v7 (though `arc` is only imported and not applied here). All shapes are rendered declaratively via JSX, with SVG circle elements and stroke styling.