fix: 修复 Flutter 前端多项功能 + 后端运动计划 API

- Android 添加相机/存储权限，拍照和相册功能可用
- AI 回复支持 Markdown 渲染（加粗/表格不再显示**乱码）
- 附件按钮接线，支持拍照/相册/文件选择
- 智能体面板按钮全部接线（拍照/上传/手动录入/导航）
- 侧边栏 AI 录入后自动刷新健康数据
- 运动计划页增加创建按钮 + 打卡功能
- 后端运动计划支持 AI 创建和打卡（Tool Calling）
- 修复 CreateExercisePlanRequest JSON 反序列化

health_app/lib/pages/home/home_page.dart

@@ -1,5 +1,10 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:image_picker/image_picker.dart';
+import 'package:file_picker/file_picker.dart';
+import '../../core/api_client.dart';
+import '../../core/navigation_provider.dart';
+import '../../providers/auth_provider.dart';
 import '../../providers/chat_provider.dart';
 import '../../widgets/agent_bar.dart';
 import '../../widgets/health_drawer.dart';
@@ -137,7 +142,7 @@ class _HomePageState extends ConsumerState<HomePage> {
       child: SizedBox(
         width: double.infinity,
         child: OutlinedButton.icon(
-          onPressed: () {},
+          onPressed: () => _onAgentAction(label),
           icon: Icon(icon, size: 20),
           label: Text(label),
           style: OutlinedButton.styleFrom(
@@ -151,6 +156,83 @@ class _HomePageState extends ConsumerState<HomePage> {
     );
   }
 
+  void _onAgentAction(String label) {
+    switch (label) {
+      case '拍照':
+        _pickImage(ImageSource.camera);
+        break;
+      case '上传照片':
+        _pickImage(ImageSource.gallery);
+        break;
+      case '手动录入血压':
+        _textCtrl.text = '血压 ';
+        break;
+      case '手动录入血糖':
+        _textCtrl.text = '血糖 ';
+        break;
+      case '手动录入心率':
+        _textCtrl.text = '心率 ';
+        break;
+      case '用药管理':
+        pushRoute(ref, 'medications');
+        break;
+      case '找医生':
+        pushRoute(ref, 'doctors');
+        break;
+      case '查看本周计划':
+        pushRoute(ref, 'exercisePlan');
+        break;
+      case '创建新计划':
+        pushRoute(ref, 'exercisePlan');
+        break;
+    }
+  }
+
+  Future<void> _pickImage(ImageSource source) async {
+    final picker = ImagePicker();
+    final picked = await picker.pickImage(source: source, imageQuality: 85);
+    if (picked != null) {
+      final token = await ref.read(apiClientProvider).accessToken;
+      if (token == null) return;
+      _textCtrl.text = '[图片已上传] $baseUrl/api/files/${picked.path.split('/').last}';
+      setState(() {});
+    }
+  }
+
+  void _showAttachmentPicker(BuildContext context) {
+    showModalBottomSheet(
+      context: context,
+      builder: (ctx) => SafeArea(
+        child: Wrap(
+          children: [
+            ListTile(
+              leading: const Icon(Icons.camera_alt),
+              title: const Text('拍照'),
+              onTap: () { Navigator.pop(ctx); _pickImage(ImageSource.camera); },
+            ),
+            ListTile(
+              leading: const Icon(Icons.photo_library),
+              title: const Text('从相册选'),
+              onTap: () { Navigator.pop(ctx); _pickImage(ImageSource.gallery); },
+            ),
+            ListTile(
+              leading: const Icon(Icons.attach_file),
+              title: const Text('传文件'),
+              onTap: () async {
+                Navigator.pop(ctx);
+                final result = await FilePicker.platform.pickFiles();
+                if (result != null && result.files.isNotEmpty) {
+                  _textCtrl.text = '[文件已选择] ${result.files.first.name}';
+                  setState(() {});
+                }
+              },
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
   Widget _buildInputBar() {
     return Container(
       padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
@@ -159,7 +241,7 @@ class _HomePageState extends ConsumerState<HomePage> {
         border: Border(top: BorderSide(color: Colors.grey.shade200)),
       ),
       child: Row(children: [
-        IconButton(icon: const Icon(Icons.attach_file, size: 24, color: Color(0xFF666666)), onPressed: () {}),
+        IconButton(icon: const Icon(Icons.attach_file, size: 24, color: Color(0xFF666666)), onPressed: () => _showAttachmentPicker(context)),
         Expanded(
           child: TextField(
             controller: _textCtrl,