Agent Skills

### Feature Request / Improvement

PyIceberg has a great CLI, which makes it a great tool for agents. I'd like to propose adding some skills that users can install with `npx skills add https://github.com/apache/iceberg-python`.

How does everyone feel about this? Does anybody have any suggestion for skills that they've built + found useful or wish existed?

未指定任何檔案、測試或進入點。先檢視現有的 PyIceberg CLI 與提議的 npx skills 安裝流程，然後釐清應包含哪些 agent skills。完成的條件是已同意 skills 的範圍，並定義出可安裝的 package。

由索引模型根據 Issue 內容生成。