style(ad_platform_config_form): remove unnecessary comment

- Removed the redundant comment "// Local Ad Management (Non-functional as requested)"
- Simplified the comment to "// Local Ad Management"

Author: fulleni

lib/app_configuration/widgets/ad_platform_config_form.dart

@@ -297,7 +297,7 @@ class _AdPlatformConfigFormState extends State<AdPlatformConfigForm> {
         ),
         const SizedBox(height: AppSpacing.lg),
 
-        // Local Ad Management (Non-functional as requested)
+        // Local Ad Management
         if (_selectedPlatform == AdPlatformType.local)
           ExpansionTile(
             title: Text(l10n.localAdManagementTitle),