refactor: 死代码清理 + 趋势图重构 + 侧边栏交互优化 + 智能体卡片去延迟

- 死代码清理: 删除 AppCard/AppMenuItem/AppTabChip/AppButtons 等 4 个未使用 Widget 文件; 清理 common_widgets/enterprise_widgets/app_status_badge 中未使用 class; 移除 HealthService 等未使用方法; 后端移除 ExerciseService.CreateFromItemsAsync/HealthArchiveService.GetOrCreateAsync/MedicationAgentHandler 死分支/ChatRequest DTO
- 趋势图: 直线折线 + 渐变填充 + 阴影; 去网格; X 轴日+月份; Y 轴整数刻度最多 4 个; 点击数据点/录入记录显示上方浮层; 选中点变实心
- 侧边栏: 对话记录改单选删除(灰底高亮); 操作栏浮层修复触摸问题; 常用功能/健康仪表盘间距收紧; _Panel 去外框
- 智能体: 欢迎卡片去掉 400ms 延迟; 胶囊去阴影
- 其他: api_client IP 适配; 多页面 UI 微调; 新增 chat_provider/prelaunch_guardrails 测试

health_app/lib/providers/chat_provider.dart

@@ -27,6 +27,7 @@ class ChatMessage {
     this.confirmed = false,
   });
   bool get isUser => role == 'user';
+  bool get isReadOnly => metadata?['readOnly'] == true;
 }
 
 enum ActiveAgent {
@@ -67,16 +68,6 @@ class ChatState {
   );
 }
 
-class SelectedAgentNotifier extends Notifier<ActiveAgent?> {
-  @override
-  ActiveAgent? build() => null;
-  void select(ActiveAgent? a) => state = a;
-}
-
-final selectedAgentProvider =
-    NotifierProvider<SelectedAgentNotifier, ActiveAgent?>(
-      SelectedAgentNotifier.new,
-    );
 final chatProvider = NotifierProvider<ChatNotifier, ChatState>(
   ChatNotifier.new,
 );
@@ -85,8 +76,8 @@ class ChatNotifier extends Notifier<ChatState> {
   StreamSubscription<Map<String, dynamic>>? _subscription;
   Completer<void>? _streamDone;
   ActiveAgent? _lastTriggeredAgent;
-
-  void markNeedsRebuild() => state = state.copyWith();
+  Timer? _agentWelcomeTimer;
+  String? _pendingAgentTriggerMessageId;
 
   /// 重置整个会话：取消正在进行的 SSE，清空消息和会话 ID。
   /// 历史记录页一键清空 / 删除当前会话时调用。
@@ -94,7 +85,6 @@ class ChatNotifier extends Notifier<ChatState> {
     await _cancelActiveStream();
     _lastTriggeredAgent = null;
     state = const ChatState();
-    ref.read(selectedAgentProvider.notifier).select(null);
   }
 
   /// 不可变消息操作方法（供 chat_messages_view 新版代码调用）
@@ -102,6 +92,7 @@ class ChatNotifier extends Notifier<ChatState> {
     final msgs = state.messages.toList();
     final i = msgs.indexWhere((m) => m.id == id);
     if (i < 0) return '确认卡片不存在';
+    if (msgs[i].isReadOnly) return '历史记录中的录入卡片仅供查看';
 
     final rawIds = msgs[i].metadata?['confirmationIds'];
     final confirmationIds = rawIds is List
@@ -142,6 +133,7 @@ class ChatNotifier extends Notifier<ChatState> {
   ChatState build() {
     ref.onDispose(() {
       _subscription?.cancel();
+      _agentWelcomeTimer?.cancel();
       _subscription = null;
       if (_streamDone != null && !_streamDone!.isCompleted) {
         _streamDone!.complete();
@@ -170,14 +162,6 @@ class ChatNotifier extends Notifier<ChatState> {
     );
   }
 
-  void setAgent(ActiveAgent a) {
-    // 流式回复中忽略胶囊切换，防止状态混乱
-    if (state.isStreaming) return;
-    _cancelActiveStream();
-    state = state.copyWith(activeAgent: a);
-    ref.read(selectedAgentProvider.notifier).select(a);
-  }
-
   /// 根据 AI 调用的工具自动切换智能体胶囊
   void _switchAgentByTool(String tool) {
     ActiveAgent? agent;
@@ -203,13 +187,13 @@ class ChatNotifier extends Notifier<ChatState> {
         break;
     }
     if (agent != null) {
-      ref.read(selectedAgentProvider.notifier).select(agent);
       state = state.copyWith(activeAgent: agent);
     }
   }
 
-  Future<void> loadConversation(String convId) async {
+  Future<String?> loadConversation(String convId) async {
     await _cancelActiveStream();
+    _cancelPendingAgentWelcome();
     try {
       final api = ref.read(apiClientProvider);
       final res = await api.get('/api/ai/conversations/$convId');
@@ -219,7 +203,8 @@ class ChatNotifier extends Notifier<ChatState> {
         final role = map['role']?.toString().toLowerCase() == 'user'
             ? 'user'
             : 'assistant';
-        final metadata = _parseMetadata(map['metadataJson']);
+        final metadata = _parseMetadata(map['metadataJson']) ?? {};
+        metadata['readOnly'] = true;
         return ChatMessage(
           id: map['id']?.toString() ?? '',
           role: role,
@@ -229,6 +214,7 @@ class ChatNotifier extends Notifier<ChatState> {
               DateTime.now(),
           type: _messageTypeFromMetadata(metadata),
           metadata: metadata,
+          confirmed: metadata['confirmationIds'] is! List,
         );
       }).toList();
 
@@ -237,11 +223,14 @@ class ChatNotifier extends Notifier<ChatState> {
         conversationId: convId,
         activeAgent: ActiveAgent.default_,
       );
-      ref.read(selectedAgentProvider.notifier).select(ActiveAgent.default_);
-    } catch (_) {}
+      return null;
+    } catch (_) {
+      return '会话加载失败，请稍后重试';
+    }
   }
 
   void insertAgentWelcome(ActiveAgent agent) {
+    _pendingAgentTriggerMessageId = null;
     state = state.copyWith(
       messages: [
         ...state.messages,
@@ -260,7 +249,12 @@ class ChatNotifier extends Notifier<ChatState> {
   /// 点击胶囊：先出用户标签 → 0.4 秒后出欢迎卡片，不走 AI
   /// 重复点击同一胶囊不重复弹卡片
   void triggerAgent(ActiveAgent agent, String label) {
-    if (_lastTriggeredAgent == agent) return;
+    if (_pendingAgentTriggerMessageId != null) {
+      return;
+    }
+    if (_lastTriggeredAgent == agent && _pendingAgentTriggerMessageId == null) {
+      return;
+    }
     _lastTriggeredAgent = agent;
 
     final userMsg = ChatMessage(
@@ -269,18 +263,35 @@ class ChatNotifier extends Notifier<ChatState> {
       content: label,
       createdAt: DateTime.now(),
     );
-    state = state.copyWith(messages: [...state.messages, userMsg]);
+    final messages = state.messages.toList();
+    messages.add(userMsg);
+    _pendingAgentTriggerMessageId = userMsg.id;
+    state = state.copyWith(messages: messages, activeAgent: agent);
+    final expectedConversationId = state.conversationId;
 
-    Future.delayed(const Duration(milliseconds: 400), () {
+    _agentWelcomeTimer = Timer(Duration.zero, () {
+      if (state.conversationId != expectedConversationId ||
+          state.activeAgent != agent ||
+          _lastTriggeredAgent != agent) {
+        return;
+      }
+      _agentWelcomeTimer = null;
       insertAgentWelcome(agent);
     });
   }
 
+  void _cancelPendingAgentWelcome() {
+    _agentWelcomeTimer?.cancel();
+    _agentWelcomeTimer = null;
+    _pendingAgentTriggerMessageId = null;
+  }
+
   Future<void> sendImage(String imagePath, String text) async {
     if (state.isStreaming) return;
     final file = File(imagePath);
     if (!await file.exists()) return;
     _lastTriggeredAgent = null;
+    _cancelPendingAgentWelcome();
 
     // 先显示用户消息（本地显示图片路径）
     final userMsg = ChatMessage(
@@ -290,7 +301,10 @@ class ChatNotifier extends Notifier<ChatState> {
       createdAt: DateTime.now(),
       metadata: {'localImagePath': imagePath},
     );
-    state = state.copyWith(messages: [...state.messages, userMsg]);
+    state = state.copyWith(
+      messages: [...state.messages, userMsg],
+      isStreaming: true,
+    );
 
     // 异步上传图片
     String? uploadedUrl;
@@ -328,6 +342,7 @@ class ChatNotifier extends Notifier<ChatState> {
         createdAt: DateTime.now(),
       );
       state = state.copyWith(messages: [...state.messages, errorMsg]);
+      state = state.copyWith(isStreaming: false);
       return;
     }
 
@@ -342,6 +357,7 @@ class ChatNotifier extends Notifier<ChatState> {
     final file = File(pdfPath);
     if (!await file.exists()) return;
     _lastTriggeredAgent = null;
+    _cancelPendingAgentWelcome();
 
     final userMsg = ChatMessage(
       id: '${DateTime.now().millisecondsSinceEpoch}',
@@ -350,7 +366,10 @@ class ChatNotifier extends Notifier<ChatState> {
       createdAt: DateTime.now(),
       metadata: {'pdfFileName': fileName},
     );
-    state = state.copyWith(messages: [...state.messages, userMsg]);
+    state = state.copyWith(
+      messages: [...state.messages, userMsg],
+      isStreaming: true,
+    );
 
     String? uploadedUrl;
     try {
@@ -382,6 +401,7 @@ class ChatNotifier extends Notifier<ChatState> {
         createdAt: DateTime.now(),
       );
       state = state.copyWith(messages: [...state.messages, errorMsg]);
+      state = state.copyWith(isStreaming: false);
       return;
     }
 
@@ -391,6 +411,7 @@ class ChatNotifier extends Notifier<ChatState> {
   Future<void> sendMessage(String text) async {
     if (text.trim().isEmpty || state.isStreaming) return;
     _lastTriggeredAgent = null;
+    _cancelPendingAgentWelcome();
 
     final userMsg = ChatMessage(
       id: '${DateTime.now().millisecondsSinceEpoch}',