refactor: 4层架构重构 + 饮食VLM接入 + 多项修复

- 后端: remaining_endpoints拆分为6个独立文件
- 后端: AI Agent Handler从ai_chat_endpoints抽取为7个独立处理器
- 后端: 食物识别prompt改为输出结构化JSON
- 前端: 饮食识别从Mock替换为真实VLM API调用
- 前端: 首页图片上传URL修复(/api/upload→/api/files/upload)
- 前端: 拍饮食按钮导航到独立DietCapturePage
- 前端: 删除无用agent_bar.dart
- 前端: 修复widget_test.dart过期属性名
- 前端: 恢复ServicePackageCard和详情页
- 新增6份实施文档(情况/问诊/报告/建档/日历/视觉统一)

health_app/test/widget_test.dart

@@ -3,14 +3,13 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:health_app/core/app_theme.dart';
 import 'package:health_app/pages/auth/login_page.dart';
-import 'package:health_app/widgets/agent_bar.dart';
 
 void main() {
   testWidgets('主题颜色正确', (tester) async {
-    expect(AppTheme.primaryColor, const Color(0xFF635BFF));
-    expect(AppTheme.background, const Color(0xFFF8F9FF));
-    expect(AppTheme.errorRed, const Color(0xFFE53935));
-    expect(AppTheme.successGreen, const Color(0xFF43A047));
+    expect(AppTheme.primary, const Color(0xFF8B9CF7));
+    expect(AppTheme.bg, const Color(0xFFF8F9FC));
+    expect(AppTheme.error, const Color(0xFFF56C6C));
+    expect(AppTheme.success, const Color(0xFF6ECF8A));
   });
 
   testWidgets('登录页渲染正常', (tester) async {
@@ -28,18 +27,6 @@ void main() {
     expect(find.text('获取验证码'), findsOneWidget);
   });
 
-  testWidgets('智能体胶囊栏渲染 6 个胶囊', (tester) async {
-    await tester.pumpWidget(const ProviderScope(child: MaterialApp(home: Scaffold(body: AgentBar()))));
-    await tester.pumpAndSettle();
-
-    expect(find.text('AI问诊'), findsOneWidget);
-    expect(find.text('记数据'), findsOneWidget);
-    expect(find.text('拍饮食'), findsOneWidget);
-    expect(find.text('药管家'), findsOneWidget);
-    expect(find.text('看报告'), findsOneWidget);
-    expect(find.text('运动计划'), findsOneWidget);
-  });
-
   testWidgets('AI 气泡样式', (tester) async {
     await tester.pumpWidget(MaterialApp(
       theme: AppTheme.lightTheme,
@@ -51,7 +38,7 @@ void main() {
           decoration: BoxDecoration(
             color: Colors.white,
             borderRadius: BorderRadius.circular(16),
-            border: const Border(left: BorderSide(color: Color(0xFF635BFF), width: 3)),
+            border: const Border(left: BorderSide(color: Color(0xFF8B9CF7), width: 3)),
           ),
           child: const Text('收到！已记录', style: TextStyle(fontSize: 16)),
         ),
@@ -70,7 +57,7 @@ void main() {
           constraints: const BoxConstraints(maxWidth: 300),
           padding: const EdgeInsets.all(16),
           decoration: BoxDecoration(
-            color: const Color(0xFF635BFF),
+            color: const Color(0xFF8B9CF7),
             borderRadius: BorderRadius.circular(16),
           ),
           child: const Text('血压 135/85', style: TextStyle(fontSize: 16, color: Colors.white)),