修复白屏BUG、UI 边界溢出 BUG

lib/features/profile/application/profile_controller.dart

@@ -17,11 +17,34 @@ class ProfileNotifier extends AsyncNotifier<UserProfile> {
   Future<UserProfile> build() async {
     final isar = await ref.watch(isarProvider.future);
     final profile = await isar.userProfiles.get(AppDefaults.singletonId);
-    if (profile != null) return profile;
-    // Bootstrap should have created one; create defensively.
-    final fresh = UserProfile.createDefault();
-    await isar.writeTxn(() => isar.userProfiles.put(fresh));
-    return fresh;
+    if (profile == null) {
+      // Bootstrap should have created one; create defensively.
+      final fresh = UserProfile.createDefault();
+      await isar.writeTxn(() => isar.userProfiles.put(fresh));
+      return fresh;
+    }
+    if (_isLocalAvatarMissing(profile)) {
+      return _clearMissingLocalAvatar(profile);
+    }
+    return profile;
+  }
+
+  bool _isLocalAvatarMissing(UserProfile profile) {
+    if (profile.avatarSource != AvatarSource.localFile) return false;
+    final path = profile.avatarLocalPath?.trim();
+    if (path == null || path.isEmpty) return true;
+    return !File(path).existsSync();
+  }
+
+  Future<UserProfile> _clearMissingLocalAvatar(UserProfile current) async {
+    final updated = current.copyWith(
+      avatarAssetPath: AppDefaults.defaultAvatarAssetPath,
+      avatarLocalPath: null,
+      avatarSource: AvatarSource.asset,
+    );
+    final isar = await ref.read(isarProvider.future);
+    await isar.writeTxn(() => isar.userProfiles.put(updated));
+    return updated;
   }
 
   Future<void> updateNickname(String nickname) async {
@@ -68,6 +91,19 @@ class ProfileNotifier extends AsyncNotifier<UserProfile> {
   Future<void> resetAvatar() async {
     final current = state.value;
     if (current == null) return;
+
+    final path = current.avatarLocalPath;
+    if (path != null && path.isNotEmpty) {
+      final file = File(path);
+      if (await file.exists()) {
+        try {
+          await file.delete();
+        } catch (_) {
+          // Best-effort cleanup; profile reset still proceeds.
+        }
+      }
+    }
+
     final updated = current.copyWith(
       avatarAssetPath: AppDefaults.defaultAvatarAssetPath,
       avatarLocalPath: null,