Make documentation embeds less ugly (#1670)

Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1670

Embeds to Yoga's documentation reuse a tiny rasterized favicon, blown up, and full of jpeg artifacts.

{F1714492025}

This bothered me enough to make the previews look better.

This change adds a quickly whipped up opengraph sized image, replaces the favicon with one derived from logo SVG, and fixes a missing description on the homepage.

 {F1714566402}

Reviewed By: yungsters

Differential Revision: D58923501

fbshipit-source-id: 249a23034f50667e32970121a90eccc380e566a3

website/docusaurus.config.js

@@ -14,7 +14,7 @@ export default {
   title: 'Yoga',
   tagline:
     'Build flexible layouts on any platform with a highly optimized open source layout engine designed with speed, size, and ease of use in mind.',
-  favicon: 'img/favicon.png',
+  favicon: 'img/favicon.svg',
 
   url: 'https:/yogalayout.dev',
   baseUrl: '/',
@@ -95,5 +95,19 @@ export default {
         defaultMode: 'dark',
         respectPrefersColorScheme: true,
       },
+      metadata: [
+        {
+          property: 'og:image',
+          content: 'https://yogalayout.dev/img/opengraph.png',
+        },
+        {
+          property: 'og:image:width',
+          content: '1200',
+        },
+        {
+          property: 'og:image:height',
+          content: '630',
+        },
+      ],
     }),
 };