fix: resolve all QA/UAT report issues (P0-P3)

Made-with: Cursor

src/App.tsx

@@ -145,6 +145,7 @@ import FaqPage from "@/pages/FaqPage";
 import NotFound from "@/pages/NotFound";
 import { queryClient } from "@/lib/query-client";
 import { Button } from "@/components/ui/button";
+import { ErrorBoundary } from "@/components/ErrorBoundary";
 
 function StudentSubscriptionPlaceholder() {
   const navigate = useNavigate();
@@ -157,6 +158,7 @@ function StudentSubscriptionPlaceholder() {
 }
 
 const App = () => (
+  <ErrorBoundary>
   <QueryClientProvider client={queryClient}>
     <TooltipProvider>
       <Toaster />
@@ -340,6 +342,7 @@ const App = () => (
       </BrowserRouter>
     </TooltipProvider>
   </QueryClientProvider>
+  </ErrorBoundary>
 );
 
 export default App;