Add some metadata for website

Author: rainxchzed

index.html

@@ -9,6 +9,12 @@
     <meta name="theme-color" content="#f4fbf7" media="(prefers-color-scheme: light)">
     <link rel="icon" type="image/png" href="https://raw.githubusercontent.com/rainxchzed/Github-Store/main/composeApp/src/commonMain/composeResources/drawable/app-icon.png">
 
+    <meta property="og:image" content="https://raw.githubusercontent.com/rainxchzed/Github-Store/refs/heads/main/screenshots/banner.jpeg">
+    <meta property="og:type" content="website">
+    <meta property="og:url" content="https://github-store.org">
+    <meta property="og:title" content="GitHub Store — Open-Source App Store">
+    <meta property="og:description" content="Discover, install, and update open-source apps directly from GitHub releases.">
+
     <link rel="preconnect" href="https://fonts.googleapis.com">
     <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
     <link href="https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&display=swap" rel="stylesheet">