refactor(ui): fix layout issues and temporarily disable auth features

- app & navbar: comment out login, register, and logout features.
- scan-page: align info cards vertically and reduce upload area padding.
- mobile-nav: implement React Portal to fix overlapping menu issue.

apps/web/src/app.tsx

@@ -5,7 +5,7 @@ import {
   Navigate,
 } from "react-router-dom";
 import { AuthInitializer } from "@/components/auth-initializer";
-import { AuthGuard } from "@/components/auth-guard";
+// import { AuthGuard } from "@/components/auth-guard";
 import { DashboardPage } from "@/pages/dashboard-page";
 import { ScanPage } from "@/pages/scan-page";
 import { LibraryPage } from "@/pages/library-page";
@@ -14,16 +14,16 @@ import { DiseaseDetailPage } from "@/pages/disease-detail-page";
 import { DiagnosisDetailPage } from "@/pages/diagnosis-detail-page";
 import { ExpertReviewsPage } from "@/pages/expert-reviews-page";
 import { DiagnosesPage } from "@/pages/diagnoses-page";
-import { LoginPage } from "@/pages/login-page";
-import { RegisterPage } from "@/pages/register-page";
+// import { LoginPage } from "@/pages/login-page";
+// import { RegisterPage } from "@/pages/register-page";
 import { MainLayout } from "@/components/layout/main-layout";
 
 const queryClient = new QueryClient();
 
 const router = createBrowserRouter([
   { path: "/", element: <Navigate to="/dashboard" replace /> },
-  { path: "/login", element: <LoginPage /> },
-  { path: "/register", element: <RegisterPage /> },
+  // { path: "/login", element: <LoginPage /> },
+  // { path: "/register", element: <RegisterPage /> },
   {
     path: "/dashboard",
     element: (
@@ -67,11 +67,9 @@ const router = createBrowserRouter([
   {
     path: "/expert/reviews",
     element: (
-      <AuthGuard requireExpert>
-        <MainLayout>
-          <ExpertReviewsPage />
-        </MainLayout>
-      </AuthGuard>
+      <MainLayout>
+        <ExpertReviewsPage />
+      </MainLayout>
     ),
   },
   {