feat: 管理后台UI全面优化 + TCP指令发送修复

- 指令页面：三个设备选择器合并为顶部统一选择器，在线/离线分组显示
- 仪表盘：8卡片压缩为6紧凑卡片，新增刷新按钮和更新时间戳
- 仪表盘：最近告警添加"查看全部"跳转链接
- 考勤页面：定位方式显示GPS/WiFi/LBS文字标签替代纯图标
- 告警页面：alarm_source中文化(单围栏/多围栏/基站/WiFi)
- 告警页面：确认操作改为DOM单行更新，无需刷新整个表格
- 数据日志：默认选中"位置"类型
- 全部表格：全选复选框tooltip改为"全选当前页"
- TCP修复：移除发送前硬性在线检查，改为尝试发送+失败提示
- TCP修复：检测僵死连接(writer.is_closing)并自动清理

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

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

app/routers/commands.py

@@ -103,12 +103,6 @@ async def _send_to_device(
     executor : async callable
         The actual send function, e.g. tcp_command_service.send_command(...)
     """
-    if not tcp_command_service.is_device_online(device.imei):
-        raise HTTPException(
-            status_code=400,
-            detail=f"Device {device.imei} is not online / 设备 {device.imei} 不在线",
-        )
-
     command_log = await command_service.create_command(
         db,
         device_id=device.id,
@@ -117,7 +111,7 @@ async def _send_to_device(
     )
 
     try:
-        await executor()
+        result = await executor()
     except Exception as e:
         logging.getLogger(__name__).error("Command send failed: %s", e)
         command_log.status = "failed"
@@ -128,6 +122,15 @@ async def _send_to_device(
             detail=fail_msg,
         )
 
+    if result is False:
+        command_log.status = "failed"
+        await db.flush()
+        await db.refresh(command_log)
+        raise HTTPException(
+            status_code=400,
+            detail=f"Device {device.imei} TCP not connected / 设备 {device.imei} TCP未连接，请等待设备重连",
+        )
+
     command_log.status = "sent"
     command_log.sent_at = now_cst()
     await db.flush()