Add og:image and social preview meta to website

- Add 1200x630 social preview image (website/public/og-image.png)
- Add og:image, og:image:width/height/alt and twitter:image meta tags

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013sSVPq8jM5vj3VFsnBEGPn

Author: claude

website/astro.config.mjs

@@ -120,6 +120,42 @@ export default defineConfig({
             content: 'light dark',
           },
         },
+        {
+          tag: 'meta',
+          attrs: {
+            property: 'og:image',
+            content: 'https://htmlhint.com/og-image.png',
+          },
+        },
+        {
+          tag: 'meta',
+          attrs: {
+            property: 'og:image:width',
+            content: '1200',
+          },
+        },
+        {
+          tag: 'meta',
+          attrs: {
+            property: 'og:image:height',
+            content: '630',
+          },
+        },
+        {
+          tag: 'meta',
+          attrs: {
+            property: 'og:image:alt',
+            content:
+              'HTMLHint: The static code analysis tool you need for your HTML',
+          },
+        },
+        {
+          tag: 'meta',
+          attrs: {
+            name: 'twitter:image',
+            content: 'https://htmlhint.com/og-image.png',
+          },
+        },
         {
           tag: 'meta',
           attrs: {