feat: 高德IoT v5 API升级、电子围栏管理、设备绑定自动考勤

- 前向地理编码升级为高德IoT v5 API (POST restapi.amap.com/v5/position/IoT)
- 修复LBS定位偏差: 添加network=LTE参数区分4G/2G, bts格式补充cage字段
- 新增电子围栏管理模块 (circle/polygon/rectangle), 支持地图绘制和POI搜索
- 新增设备-围栏多对多绑定 (DeviceFenceBinding/DeviceFenceState)
- 围栏自动考勤引擎 (fence_checker.py): haversine距离、ray-casting多边形判定、容差机制、防抖
- TCP位置上报自动检测围栏进出, 生成考勤记录并WebSocket广播
- 前端围栏页面: 绑定设备弹窗、POI搜索定位、左侧围栏面板
- 新增fence_attendance WebSocket topic

via [HAPI](https://hapi.run)

Co-Authored-By: HAPI <noreply@hapi.run>

app/routers/locations.py

@@ -7,9 +7,10 @@ import math
 from datetime import datetime
 
 from fastapi import APIRouter, Body, Depends, HTTPException, Query
-from sqlalchemy import select
+from sqlalchemy import select, delete
 from sqlalchemy.ext.asyncio import AsyncSession
 
+from app.dependencies import require_write
 from app.database import get_db
 from app.models import LocationRecord
 from app.schemas import (
@@ -153,3 +154,22 @@ async def get_location(location_id: int, db: AsyncSession = Depends(get_db)):
     if record is None:
         raise HTTPException(status_code=404, detail=f"Location {location_id} not found")
     return APIResponse(data=LocationRecordResponse.model_validate(record))
+
+
+@router.delete(
+    "/{location_id}",
+    response_model=APIResponse,
+    summary="删除位置记录 / Delete location record",
+    dependencies=[Depends(require_write)],
+)
+async def delete_location(location_id: int, db: AsyncSession = Depends(get_db)):
+    """按ID删除位置记录 / Delete location record by ID."""
+    result = await db.execute(
+        select(LocationRecord).where(LocationRecord.id == location_id)
+    )
+    record = result.scalar_one_or_none()
+    if record is None:
+        raise HTTPException(status_code=404, detail=f"Location {location_id} not found")
+    await db.delete(record)
+    await db.flush()
+    return APIResponse(message="Location record deleted")