Add 404 redirect handling and GitHub Pages workflow configuration

index.html

@@ -12,5 +12,15 @@
     <div id="app"></div>
 
     <script type="module" src="/src/main.ts"></script>
+    <script>
+      // Redirects user from 404
+      (function () {
+        var redirect = sessionStorage.redirect;
+        delete sessionStorage.redirect;
+        if (redirect && redirect != location.href) {
+          history.replaceState(null, null, redirect);
+        }
+      })();
+    </script>
   </body>
 </html>