chore: add structural semantic comment to app root

Author: PrinceBad

index.html

@@ -11,6 +11,7 @@
     <link href="https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;500;600;700;800&family=Playfair+Display:ital,wght@0,400;0,600;0,700;1,400&family=Fira+Code:wght@400;500&display=swap" rel="stylesheet">
   </head>
   <body>
+    <!-- TubeNotes App Root -->
     <div id="root"></div>
     <script type="module" src="/src/main.jsx"></script>
   </body>