feat: setup 'web' frontend

web/pages/_error/+Page.tsx

@@ -0,0 +1,19 @@
+import { usePageContext } from "vike-react/usePageContext";
+
+export default function Page() {
+  const { is404 } = usePageContext();
+  if (is404) {
+    return (
+      <>
+        <h1>Page Not Found</h1>
+        <p>This page could not be found.</p>
+      </>
+    );
+  }
+  return (
+    <>
+      <h1>Internal Error</h1>
+      <p>Something went wrong.</p>
+    </>
+  );
+}