功能：area_id 存储 + 工单对接代码完善 + 心跳端点

- AlarmEvent 模型添加 area_id 字段
- create_from_edge_report 提取 ext_data.area_id 存储
- 心跳端点 POST /api/ai/device/heartbeat
- work_order_client: create_order 支持完整参数（description/priority/triggerSource/cameraId/imageUrl）
- notify_dispatch: 工单标题中文化、alarmType 中文映射、永久 COS URL、triggerSource 来源判断
- oss_storage: 新增 get_permanent_url 方法
- 工单创建测试脚本

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/services/work_order_client.py

@@ -80,10 +80,26 @@ class WorkOrderClient:
         area_id: int,
         alarm_id: str,
         alarm_type: str,
+        description: str = "",
+        priority: Optional[int] = None,
+        trigger_source: str = "自动上报",
+        camera_id: str = "",
+        image_url: str = "",
     ) -> Optional[str]:
         """
         创建安保工单
 
+        Args:
+            title: 工单标题（中文告警类型，如"人员离岗告警"）
+            area_id: 区域ID
+            alarm_id: 告警ID
+            alarm_type: 告警类型编码（leave_post/intrusion等）
+            description: VLM 大模型描述
+            priority: 优先级（0紧急 1重要 2普通 3轻微）
+            trigger_source: 来源（自动上报/人工上报）
+            camera_id: 摄像头ID
+            image_url: 截图URL
+
         Returns:
             orderId 字符串，失败返回 None
         """
@@ -97,6 +113,17 @@ class WorkOrderClient:
             "alarmId": alarm_id,
             "alarmType": alarm_type,
         }
+        if description:
+            body["description"] = description
+        if priority is not None:
+            body["priority"] = priority
+        if trigger_source:
+            body["triggerSource"] = trigger_source
+        if camera_id:
+            body["cameraId"] = camera_id
+        if image_url:
+            body["imageUrl"] = image_url
+
         body_json = json.dumps(body, ensure_ascii=False, separators=(",", ":"))
 
         try: