mark entry point custom element when returning metadata

[thescientist13]

Type of Change

• New Feature Request

Summary

It would be great for returned metadata to mark the initial custom element as the entry point, which can be helpful for more app like usages of WCC.

Details

For example

const { metadata } = await renderToString(new URL('./src/pages/home.js', import.meta.url));

/*
 * {
 *   metadata: [
 *     'wcc-home': { instanceName: 'HomePage', moduleURL: [URL], entry: true },
 *     'wcc-footer': { instanceName: 'Footer', moduleURL: [URL] },
 *     'wcc-header': { instanceName: 'Header', moduleURL: [URL] },
 *     'wcc-navigation': { instanceName: 'Navigation', moduleURL: [URL] }
 *   ]
 * }
 *

However, if there is no tagName provided, like for a layout route or page, the next level of custom elements should be used instead.