How do you properly measure and meaningfully improve a Flutter web app's own Core Web Vitals metrics, such as Largest Contentful Paint and Cumulative Layout Shift, which meaningfully affect both overall user experience and its actual search engine ranking?

Core Web Vitals are a genuinely specific, well established set of standardized metrics that Google actually uses to help meaningfully assess a given web page's own overall real user experience, and improving these particular metrics specifically for a Flutter web app typically involves meaningfully reducing the initial time until meaningful content genuinely first appears through techniques including deferred loading and properly optimizing your overall bundle size, carefully avoiding any genuinely unexpected layout shifts by properly reserving appropriate space for images and other genuinely asynchronously loaded content before it has actually genuinely fully finished loading, and using tools such as Google's own Lighthouse to properly and thoroughly measure your genuine actual current performance and then properly identify exactly where your very best specific improvement opportunities genuinely actually lie.

// Reserving appropriate space for an image before it has genuinely finished loading
SizedBox(width: 300, height: 200, child: Image.network(url))