perf: defer initial data fetching to microtasks and update loading placeholders for smoother screen transitions

lib/features/about/presentation/screens/about_screen.dart

@@ -206,7 +206,8 @@ class _AboutState {
 
 class _AboutNotifier extends StateNotifier<_AboutState> {
   _AboutNotifier() : super(const _AboutState()) {
-    _load();
+    // Defer CMS fetch so the first frame paints before the HTTP request
+    Future.microtask(_load);
   }
 
   Future<void> _load() async {
@@ -304,9 +305,18 @@ class AboutScreen extends ConsumerWidget {
     final state = ref.watch(_aboutProvider);
 
     if (state.isLoading) {
-      return const Center(
-        child: CircularProgressIndicator(
-          color: AppColors.accentOrange,
+      // Full-size placeholder so slide-in transition doesn't pop blank
+      return Container(
+        color: Colors.white,
+        alignment: Alignment.topCenter,
+        padding: const EdgeInsets.only(top: 120),
+        child: const SizedBox(
+          width: 28,
+          height: 28,
+          child: CircularProgressIndicator(
+            color: AppColors.accentOrange,
+            strokeWidth: 2.5,
+          ),
         ),
       );
     }