[DISCUSS] We have some C++ code to share for Iceberg read/write

Just a quick note, we are open-sourcing our C++ implementation for Iceberg read/write, starting from this "small" PR: https://github.com/timeplus-io/proton/pull/928

It supports Iceberg REST Catalog (verified with AWS Glue, WIP for Polaris and Gravitino). Primarily for S3 storage (half-done with new S3 table). Streaming writes and batch read.

We leveraged some code from ClickHouse. Happy to work with you to contribute in one way or the other.

首先查看所引用的 proton PR 928 以及 Iceberg C++ repository 的相关背景。该 issue 描述了一个可能涉及 REST Catalog 支持、S3 存储、流式写入和批量读取的贡献，但没有指出文件、测试或明确定义的验收标准。开始之前，请与维护者确认预期的贡献范围。

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