[Bug] raft添加节点失败

### Bug Type (问题类型)

other exception / error (其他异常报错)

### Before submit

- [X] 我已经确认现有的 [Issues](https://github.com/hugegraph/hugegraph/issues) 与 [FAQ](https://hugegraph.github.io/hugegraph-doc/guides/faq.html) 中没有相同 / 重复问题

### Environment (环境信息)

- Server Version: v1.0.0
- Backend: RocksDB x nodes, HDD or SSD
- OS: xx CPUs, xx G RAM, Centos 7.x
- Data Size: xx vertices, xx edges

### Expected & Actual behavior (期望与实际表现)

**在向raft集群持续写入数据的过程中**，无法完成新节点的加入（`bin/raft-tools -a graph_name xxx`）
新节点报错如下：

**停止数据写入后**，重新操作添加新节点，成功。

也就是说，在数据写入的过程中，raft集群无法新增peer；停止数据写入，raft集群可以新增peer

测试多次，该问题必现

### Vertex/Edge example (问题点 / 边数据举例)

_No response_

### Schema [VertexLabel, EdgeLabel, IndexLabel] (元数据结构)

_No response_

Start with the `bin/raft-tools -a graph_name xxx` add-node operation and reproduce it while the cluster is receiving continuous writes; inspect the reported new-node error in the linked screenshot. Done means a new peer can be added successfully without stopping writes, with the behavior verified across repeated tests.

Written by the indexing model from the issue text.