Refactor API response handling across multiple components to ensure consistency with the unified format. Update error handling and response validation in ValidationCard, usePersistentToggle, Status, Prompts, and api.ts to improve user feedback and maintain compatibility with the new API standards.

frontend/src/pages/Settings/Status.tsx

@@ -63,10 +63,10 @@ export default function Status() {
 
   const fetchStatus = async () => {
     try {
+      // fetchAPI extracts data from unified format {success: true, data: {...}}
+      // So response IS the data object
       const response = await fetchAPI('/v1/system/status/');
-      // Handle unified API response format: {success: true, data: {...}}
-      const statusData = response?.data || response;
-      setStatus(statusData);
+      setStatus(response);
       setError(null);
     } catch (err) {
       setError(err instanceof Error ? err.message : 'Unknown error');