perf(mobile-app): optimize avatar loading with parallel fetch and file caching

- Use Future.wait for parallel data loading (faster initial load)
- Add file.existsSync() check before using Image.file
- Add cacheWidth/cacheHeight and gaplessPlayback for smoother display
- Add _checkLocalAvatarSync for early avatar path detection

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/mobile-app/lib/features/mining/presentation/pages/mining_page.dart

@@ -36,17 +36,40 @@ class _MiningPageState extends ConsumerState<MiningPage> {
   @override
   void initState() {
     super.initState();
+    // 先同步检查本地头像，再异步加载其他数据
+    _checkLocalAvatarSync();
     _loadUserData();
   }
 
+  /// 同步检查本地头像文件（在 build 之前快速获取）
+  void _checkLocalAvatarSync() {
+    WidgetsBinding.instance.addPostFrameCallback((_) async {
+      final accountService = ref.read(accountServiceProvider);
+      final localPath = await accountService.getLocalAvatarPath();
+      if (mounted && localPath != null && _localAvatarPath == null) {
+        setState(() {
+          _localAvatarPath = localPath;
+        });
+      }
+    });
+  }
+
   /// 加载用户数据
   Future<void> _loadUserData() async {
     final accountService = ref.read(accountServiceProvider);
 
-    final serialNum = await accountService.getUserSerialNum();
+    // 并行加载所有数据
-    final avatarSvg = await accountService.getAvatarSvg();
+    final results = await Future.wait([
-    final avatarUrl = await accountService.getAvatarUrl();
+      accountService.getUserSerialNum(),
-    final localAvatarPath = await accountService.getLocalAvatarPath();
+      accountService.getAvatarSvg(),
+      accountService.getAvatarUrl(),
+      accountService.getLocalAvatarPath(),
+    ]);
+
+    final serialNum = results[0] as int?;
+    final avatarSvg = results[1] as String?;
+    final avatarUrl = results[2] as String?;
+    final localAvatarPath = results[3] as String?;
 
     if (mounted) {
       setState(() {
@@ -386,16 +409,22 @@ class _MiningPageState extends ConsumerState<MiningPage> {
     // 1. 优先显示本地缓存的头像文件
     if (_localAvatarPath != null && _localAvatarPath!.isNotEmpty) {
       final file = File(_localAvatarPath!);
-      return Image.file(
+      // 同步检查文件是否存在
-        file,
+      if (file.existsSync()) {
-        width: 80,
+        return Image.file(
-        height: 80,
+          file,
-        fit: BoxFit.cover,
+          width: 80,
-        errorBuilder: (context, error, stackTrace) {
+          height: 80,
-          // 本地文件加载失败，尝试网络URL
+          fit: BoxFit.cover,
-          return _buildNetworkOrSvgAvatar();
+          cacheWidth: 160, // 2x 分辨率缓存，提升性能
-        },
+          cacheHeight: 160,
-      );
+          gaplessPlayback: true, // 防止图片切换时闪烁
+          errorBuilder: (context, error, stackTrace) {
+            // 本地文件加载失败，尝试网络URL
+            return _buildNetworkOrSvgAvatar();
+          },
+        );
+      }
     }
 
     // 2. 没有本地缓存，尝试网络URL或SVG

frontend/mobile-app/lib/features/profile/presentation/pages/profile_page.dart

@@ -64,18 +64,43 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
   void initState() {
     super.initState();
     _startCountdown();
+    // 先同步检查本地头像，再异步加载其他数据
+    _checkLocalAvatarSync();
     _loadUserData();
   }
 
+  /// 同步检查本地头像文件（在 build 之前快速获取）
+  void _checkLocalAvatarSync() {
+    // 使用 WidgetsBinding 确保在第一帧渲染前执行
+    WidgetsBinding.instance.addPostFrameCallback((_) async {
+      final accountService = ref.read(accountServiceProvider);
+      final localPath = await accountService.getLocalAvatarPath();
+      if (mounted && localPath != null && _localAvatarPath == null) {
+        setState(() {
+          _localAvatarPath = localPath;
+        });
+      }
+    });
+  }
+
   /// 加载用户数据
   Future<void> _loadUserData() async {
     final accountService = ref.read(accountServiceProvider);
 
-    final username = await accountService.getUsername();
+    // 并行加载所有数据
-    final serialNum = await accountService.getUserSerialNum();
+    final results = await Future.wait([
-    final avatarSvg = await accountService.getAvatarSvg();
+      accountService.getUsername(),
-    final avatarUrl = await accountService.getAvatarUrl();
+      accountService.getUserSerialNum(),
-    final localAvatarPath = await accountService.getLocalAvatarPath();
+      accountService.getAvatarSvg(),
+      accountService.getAvatarUrl(),
+      accountService.getLocalAvatarPath(),
+    ]);
+
+    final username = results[0] as String?;
+    final serialNum = results[1] as int?;
+    final avatarSvg = results[2] as String?;
+    final avatarUrl = results[3] as String?;
+    final localAvatarPath = results[4] as String?;
 
     if (mounted) {
       setState(() {
@@ -365,16 +390,22 @@ class _ProfilePageState extends ConsumerState<ProfilePage> {
     // 1. 优先显示本地缓存的头像文件
     if (_localAvatarPath != null && _localAvatarPath!.isNotEmpty) {
       final file = File(_localAvatarPath!);
-      return Image.file(
+      // 同步检查文件是否存在
-        file,
+      if (file.existsSync()) {
-        width: 80,
+        return Image.file(
-        height: 80,
+          file,
-        fit: BoxFit.cover,
+          width: 80,
-        errorBuilder: (context, error, stackTrace) {
+          height: 80,
-          // 本地文件加载失败，尝试网络URL
+          fit: BoxFit.cover,
-          return _buildNetworkOrSvgAvatar();
+          cacheWidth: 160, // 2x 分辨率缓存，提升性能
-        },
+          cacheHeight: 160,
-      );
+          gaplessPlayback: true, // 防止图片切换时闪烁
+          errorBuilder: (context, error, stackTrace) {
+            // 本地文件加载失败，尝试网络URL
+            return _buildNetworkOrSvgAvatar();
+          },
+        );
+      }
     }
 
     // 2. 没有本地缓存，尝试网络URL或SVG