perf: optimize home screen rendering with ListView.builder and improve image loading performance by persisting disk cache

lib/core/widgets/s3_image.dart

@@ -112,6 +112,8 @@ class _S3ImageState extends State<S3Image> {
       height: widget.height,
       fit: widget.fit,
       alignment: widget.alignment,
+      fadeInDuration: const Duration(milliseconds: 200),
+      fadeOutDuration: const Duration(milliseconds: 100),
       placeholder: (ctx, _) => _buildPlaceholder(ctx),
       errorWidget: (ctx, _, err) {
         // On error (expired URL), evict and retry once

lib/features/home/presentation/screens/home_screen.dart

@@ -21,31 +21,25 @@ class HomeScreen extends ConsumerWidget {
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     final scrollController = ref.watch(homeScrollControllerProvider);
-    return SingleChildScrollView(
-      controller: scrollController,
-      child: Column(
-        children: [
-          // Hero Section with Search
-          const HeroSection(),
+    // Use ListView.builder for lazy rendering — only builds sections as
+    // they scroll into view, instead of rendering all 5 heavy sections at
+    // once in a Column (which causes jank on initial load).
+    final sections = <Widget>[
+      const RepaintBoundary(child: HeroSection()),
       const SizedBox(height: 40),
-
-          // Features Section
-          const FeaturesSection(),
+      const RepaintBoundary(child: FeaturesSection()),
       const SizedBox(height: 40),
-
-          // Top Professionals Section (Agents/Lenders tabs)
-          const TopProfessionalsSection(),
+      const RepaintBoundary(child: TopProfessionalsSection()),
       const SizedBox(height: 40),
-
-          // Trust & Stats Section
-          const TrustStatsSection(),
+      const RepaintBoundary(child: TrustStatsSection()),
       const SizedBox(height: 24),
-
-          // Testimonials Section
-          const TestimonialsSection(),
+      const RepaintBoundary(child: TestimonialsSection()),
       const SizedBox(height: 40),
-        ],
-      ),
+    ];
+    return ListView.builder(
+      controller: scrollController,
+      itemCount: sections.length,
+      itemBuilder: (_, i) => sections[i],
     );
   }
 

lib/main.dart

@@ -1,7 +1,5 @@
-import 'package:cached_network_image/cached_network_image.dart';
 import 'package:firebase_core/firebase_core.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter_cache_manager/flutter_cache_manager.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:real_estate_mobile/config/app_config.dart';
 import 'package:real_estate_mobile/config/firebase_config.dart';
@@ -15,13 +13,12 @@ Future<void> mainCommon(Flavor flavor) async {
 
   await Firebase.initializeApp(options: FirebaseConfig.currentOptions);
 
-  // Clear stale image caches on app start to ensure fresh presigned URLs
+  // Only clear the in-memory presigned URL cache — NOT the disk image cache.
+  // Presigned URLs expire after ~1 hour and are re-fetched lazily by
+  // ImageUrlResolver when needed. The disk cache (CachedNetworkImage) must
+  // persist across restarts for app smoothness — clearing it on every start
+  // forces every image to re-download, causing visible delay on all screens.
   ImageUrlResolver.instance.clearCache();
-  PaintingBinding.instance.imageCache.clear();
-  PaintingBinding.instance.imageCache.clearLiveImages();
-  // Also clear CachedNetworkImage disk cache so old presigned URLs
-  // (which may point to stale/wrong images) don't persist across sessions.
-  DefaultCacheManager().emptyCache();
 
   runApp(const ProviderScope(child: MyApp()));
 }