Enhance billing and subscription management: Added payment method checks in ProtectedRoute, improved error handling in billing components, and optimized API calls to reduce throttling. Updated user account handling in various components to ensure accurate plan and subscription data display.

frontend/src/components/common/ModuleGuard.tsx

@@ -2,6 +2,7 @@ import { ReactNode, useEffect } from 'react';
 import { Navigate } from 'react-router-dom';
 import { useSettingsStore } from '../../store/settingsStore';
 import { isModuleEnabled } from '../../config/modules.config';
+import { isUpgradeError } from '../../utils/upgrade';
 
 interface ModuleGuardProps {
   module: string;