fix: 健康档案保存按钮移至右上角 + 5页面补充返回按钮 + API地址修复

- 健康档案: 保存按钮移到AppBar右侧，删除底部按钮和绿色成功SnackBar
- 5个缺失页面补充左上角返回按钮: 健康概览/编辑用药/报告管理/报告详情/报告解读
- api_client.dart: 默认baseUrl改为192.168.1.29 (支持WiFi直连)

health_app/lib/pages/chart/trend_page.dart

@@ -3,6 +3,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import '../../core/app_colors.dart';
 import '../../core/app_theme.dart';
+import '../../core/navigation_provider.dart';
 import '../../providers/auth_provider.dart';
 import '../../providers/data_providers.dart';
 
@@ -247,7 +248,11 @@ class _TrendPageState extends ConsumerState<TrendPage> {
   @override
   Widget build(BuildContext context) {
     return GradientScaffold(
-      appBar: AppBar(title: const Text('健康概览'), centerTitle: true),
+      appBar: AppBar(
+        leading: IconButton(icon: const Icon(Icons.arrow_back), onPressed: () => popRoute(ref)),
+        title: const Text('健康概览'),
+        centerTitle: true,
+      ),
       floatingActionButton: FloatingActionButton(
         onPressed: _showAddDialog,
         backgroundColor: _color,