feat: UI清爽紫蓝风全面改造 + 对话卡片重构 + 配色体系升级

- 新增 AppColors 统一配色方案（清爽紫蓝，参考蚂蚁阿福风格）
- 新增 common_widgets（GradientBorderButton / CardActionButton / IconBox）
- AgentWelcomeCard 美化：渐变 header + AI标签 + 核心功能区 + 快捷操作区
- DataConfirmCard 统一：三合一（健康/药品/运动），可编辑字段列表
- 删除死代码：medicationConfirm/dietAnalysis/reportAnalysis/quickOptions 卡片
- 删除死路由：doctors/profileEdit/editProfile
- AI 对话去除 Markdown 符号（_stripMd），统一行间距 1.5
- 逐字淡入动画修复：key 改用 stableId 避免重复触发
- 健康概览时间修复：前端发送 UTC 避免时区歧义
- PG 数据目录迁入项目 backend/pgdata/，加入 .gitignore
- 新增欧姆龙血压计实施方案文档

health_app/lib/providers/chat_provider.dart

@@ -5,7 +5,7 @@ import 'auth_provider.dart';
 import 'data_providers.dart';
 import '../utils/sse_handler.dart';
 
-enum MessageType { text, dataConfirm, medicationConfirm, dietAnalysis, reportAnalysis, quickOptions, agentWelcome, taskCard }
+enum MessageType { text, dataConfirm, agentWelcome, taskCard }
 
 class ChatMessage {
   final String id;
@@ -77,6 +77,8 @@ ActiveAgent _parseAgent(String? type) {
 
 class ChatNotifier extends Notifier<ChatState> {
   StreamSubscription<Map<String, dynamic>>? _subscription;
+  String _streamBuffer = '';
+  Timer? _streamTimer;
 
   void markNeedsRebuild() => state = state.copyWith();
 
@@ -174,6 +176,23 @@ class ChatNotifier extends Notifier<ChatState> {
     )]);
   }
 
+  /// 点击胶囊：先出用户标签 → 0.5 秒后出欢迎卡片，不走 AI
+  void triggerAgent(ActiveAgent agent, String label) {
+    final userMsg = ChatMessage(
+      id: 'agent_trigger_${DateTime.now().millisecondsSinceEpoch}',
+      role: 'user',
+      content: label,
+      createdAt: DateTime.now(),
+    );
+    // 先出用户消息
+    state = state.copyWith(messages: [...state.messages, userMsg]);
+
+    // 短暂延迟后弹出卡片
+    Future.delayed(const Duration(milliseconds: 400), () {
+      insertAgentWelcome(agent);
+    });
+  }
+
   Future<void> sendImage(String imagePath, String text) async {
     final file = File(imagePath);
     if (!await file.exists()) return;
@@ -241,7 +260,8 @@ class ChatNotifier extends Notifier<ChatState> {
       createdAt: DateTime.now(),
     );
 
-    state = state.copyWith(isStreaming: true);
+    // 立即加入空 AI 消息，让思考动画有载体
+    state = state.copyWith(messages: [...state.messages, aiMsg], isStreaming: true);
 
     try {
       final token = await ref.read(apiClientProvider).accessToken;
@@ -288,15 +308,21 @@ class ChatNotifier extends Notifier<ChatState> {
       case 'conversation_id':
         state = state.copyWith(conversationId: j['data']?.toString());
       case 'answer':
-        aiMsg.content += (j['data'] as String?) ?? '';
+        _streamBuffer += (j['data'] as String?) ?? '';
         final messageType = j['type'] as String? ?? 'text';
         aiMsg.type = _parseMessageType(messageType);
-        // 从 SSE 中获取元数据（用药/健康数据的确认信息）
         if (j['metadata'] is Map) {
           aiMsg.metadata = Map<String, dynamic>.from(j['metadata']);
         }
-        state = state.copyWith(thinkingText: null);
-        _update(aiMsg);
+        // 逐字释放
+        _streamTimer?.cancel();
+        _streamTimer = Timer.periodic(const Duration(milliseconds: 40), (t) {
+          if (_streamBuffer.isEmpty) { t.cancel(); state = state.copyWith(thinkingText: null); return; }
+          aiMsg.content += _streamBuffer[0];
+          _streamBuffer = _streamBuffer.substring(1);
+          state = state.copyWith(thinkingText: null);
+          _update(aiMsg);
+        });
       case 'notice':
         state = state.copyWith(thinkingText: j['message'] as String?);
       case 'tool_result':
@@ -315,13 +341,13 @@ class ChatNotifier extends Notifier<ChatState> {
 
   MessageType _parseMessageType(String type) {
     switch (type) {
-      case 'data_confirm': return MessageType.dataConfirm;
-      case 'medication_confirm': return MessageType.medicationConfirm;
-      case 'diet_analysis': return MessageType.dietAnalysis;
-      case 'report_analysis': return MessageType.reportAnalysis;
-      case 'quick_options': return MessageType.quickOptions;
-      case 'agent_welcome': return MessageType.agentWelcome;
-      default: return MessageType.text;
+      case 'data_confirm':
+      case 'medication_confirm':
+        return MessageType.dataConfirm;
+      case 'agent_welcome':
+        return MessageType.agentWelcome;
+      default:
+        return MessageType.text;
     }
   }
 
@@ -330,13 +356,19 @@ class ChatNotifier extends Notifier<ChatState> {
     final i = u.indexWhere((x) => x.id == m.id);
     if (i >= 0) {
       u[i] = m;
-    } else if (m.content.isNotEmpty) {
-      u.add(m);
+    } else {
+      u.add(m); // 空内容也加入，让思考气泡有载体
     }
     state = state.copyWith(messages: u);
   }
 
   void _done(ChatMessage m) {
+    _streamTimer?.cancel();
+    // 释放剩余 buffer
+    while (_streamBuffer.isNotEmpty) {
+      m.content += _streamBuffer[0];
+      _streamBuffer = _streamBuffer.substring(1);
+    }
     final u = state.messages.toList();
     if (!u.any((x) => x.id == m.id) && m.content.isNotEmpty) u.add(m);
     state = state.copyWith(messages: u, isStreaming: false, thinkingText: null);