feat: AI 对话附件上下文解析 + 历史会话归档 + 多页面 UI 重构

- 后端: 新增 AttachmentContextBuilder 解析图片/PDF 摘要并拼入 LLM 上下文; ai_chat_endpoints 扩展附件接口; 新增 ReportAnalysisService
- 前端: 新增历史会话页与 conversation_history_provider; chat 链路支持附件展示与回放
- UI: 重构 medication_checkin / notification_center / profile / health_drawer 等多页面
- 配置: api_client baseUrl 适配当前 WiFi IP

health_app/lib/pages/device/device_scan_page.dart

@@ -393,16 +393,32 @@ class _DeviceResultTile extends StatelessWidget {
     final type = HealthBleService.deviceTypeFromScan(result);
     final name = _deviceNameOf(result, type);
     return Container(
-      padding: const EdgeInsets.all(14),
+      padding: const EdgeInsets.all(15),
       decoration: BoxDecoration(
         color: Colors.white,
-        borderRadius: BorderRadius.circular(12),
-        border: Border.all(color: AppColors.borderLight),
+        borderRadius: BorderRadius.circular(16),
+        border: Border.all(color: AppColors.border, width: 1.1),
+        boxShadow: [AppTheme.shadowLight],
       ),
       child: Row(
         children: [
-          Icon(type?.icon ?? Icons.bluetooth_rounded, color: AppColors.primary),
-          const SizedBox(width: 12),
+          Container(
+            width: 48,
+            height: 48,
+            decoration: BoxDecoration(
+              color: AppColors.primary.withValues(alpha: 0.10),
+              borderRadius: BorderRadius.circular(14),
+              border: Border.all(
+                color: AppColors.primary.withValues(alpha: 0.10),
+              ),
+            ),
+            child: Icon(
+              type?.icon ?? Icons.bluetooth_rounded,
+              color: AppColors.primary,
+              size: 25,
+            ),
+          ),
+          const SizedBox(width: 14),
           Expanded(
             child: Column(
               crossAxisAlignment: CrossAxisAlignment.start,
@@ -410,27 +426,41 @@ class _DeviceResultTile extends StatelessWidget {
                 Text(
                   type?.label ?? '健康设备',
                   style: const TextStyle(
-                    fontSize: 15,
+                    fontSize: 18,
                     fontWeight: FontWeight.w800,
                     color: AppColors.textPrimary,
                   ),
                 ),
-                const SizedBox(height: 3),
+                const SizedBox(height: 4),
                 Text(
                   name,
                   maxLines: 1,
                   overflow: TextOverflow.ellipsis,
                   style: const TextStyle(
-                    fontSize: 12,
+                    fontSize: 14,
                     color: AppColors.textHint,
                   ),
                 ),
               ],
             ),
           ),
-          FilledButton(
-            onPressed: connecting ? null : onConnect,
-            child: Text(connecting ? '连接中' : '连接'),
+          const SizedBox(width: 10),
+          SizedBox(
+            height: 38,
+            child: FilledButton(
+              onPressed: connecting ? null : onConnect,
+              style: FilledButton.styleFrom(
+                padding: const EdgeInsets.symmetric(horizontal: 14),
+                shape: RoundedRectangleBorder(
+                  borderRadius: BorderRadius.circular(10),
+                ),
+                textStyle: const TextStyle(
+                  fontSize: 14,
+                  fontWeight: FontWeight.w800,
+                ),
+              ),
+              child: Text(connecting ? '连接中' : '连接'),
+            ),
           ),
         ],
       ),