feat: 信标设备绑定 + 蓝牙模式管理 + 系统管理增强 + 数据导出

- 新增 DeviceBeaconBinding 模型，信标-设备多对多绑定 CRUD
- 蓝牙打卡模式批量配置/恢复正常模式 API
- 反向同步: 查询设备 BTMACSET 配置更新数据库绑定 (独立 session 解决事务隔离)
- 设备列表快捷操作弹窗修复 (fire-and-forget IIFE 替代阻塞轮询)
- 保存按钮防抖: 围栏/信标绑定保存点击后 disabled + 转圈防重复提交
- 审计日志中间件 + 系统配置/备份/固件 API
- 设备分组管理 + 告警规则配置
- 5个数据导出 API (CSV UTF-8 BOM)
- 位置热力图 + 告警条件删除 + 位置清理

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

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

app/routers/devices.py

@@ -6,9 +6,13 @@ API endpoints for device CRUD operations and statistics.
 import math
 
 from fastapi import APIRouter, Depends, HTTPException, Query, Request
+from fastapi.responses import Response
+from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.database import get_db
+from app.models import Device
+from app.services.export_utils import build_csv_content, csv_filename
 from app.schemas import (
     APIResponse,
     BatchDeviceCreateRequest,
@@ -74,6 +78,40 @@ async def device_stats(db: AsyncSession = Depends(get_db)):
     return APIResponse(data=stats)
 
 
+@router.get(
+    "/export",
+    summary="导出设备列表 CSV / Export devices CSV",
+)
+async def export_devices(
+    status: str | None = Query(default=None, description="状态过滤 (online/offline)"),
+    search: str | None = Query(default=None, description="搜索IMEI或名称"),
+    db: AsyncSession = Depends(get_db),
+):
+    """导出设备列表为 CSV 文件，支持状态/搜索筛选。"""
+    from sqlalchemy import or_
+
+    query = select(Device)
+    if status:
+        query = query.where(Device.status == status)
+    if search:
+        pattern = f"%{search}%"
+        query = query.where(or_(Device.imei.ilike(pattern), Device.name.ilike(pattern)))
+    query = query.order_by(Device.id)
+
+    result = await db.execute(query)
+    devices = list(result.scalars().all())
+
+    headers = ["ID", "IMEI", "名称", "类型", "状态", "电量%", "信号", "ICCID", "IMSI", "最后心跳", "最后登录", "创建时间"]
+    fields = ["id", "imei", "name", "device_type", "status", "battery_level", "gsm_signal", "iccid", "imsi", "last_heartbeat", "last_login", "created_at"]
+
+    content = build_csv_content(headers, devices, fields)
+    return Response(
+        content=content,
+        media_type="text/csv; charset=utf-8",
+        headers={"Content-Disposition": f"attachment; filename={csv_filename('devices')}"},
+    )
+
+
 @router.get(
     "/imei/{imei}",
     response_model=APIResponse[DeviceResponse],