[Feature request] 能否IoTDB 在高并发的环境下写入性能优化一下

### Search before asking

- [X] I searched in the [issues](https://github.com/apache/iotdb/issues) and found nothing similar.

### Motivation

在高并发环境下（如 500 个并发客户端），IoTDB 写入性能显著下降。希望开发团队优化高并发写入场景下的数据库性能。

### Solution

_No response_

### Alternatives

_No response_

### Are you willing to submit a PR?

- [X] I'm willing to submit a PR!

No file, test, or entry point is named. Start by locating IoTDB's concurrent write path and establish a reproducible benchmark with the reported 500-client workload. Done should mean a documented, measurable improvement in high-concurrency write performance, with regression coverage or benchmark results.

Written by the indexing model from the issue text.