Use parent realm's copy of rubico for the code runners

At the moment, it's fetching every run and the examples are sometimes loading slowly. I've noticed on a fresh cache it was the first run that was slow and subsequent runs for different examples were quicker. Perhaps some caching is being done in the browser to that end. The relevant file should be `/CodeRunner.js`.

Note: Might have to perform a light refactor of the code runners to Realms first

该 issue 提到了文档网站中代码运行器的性能改进，具体是从父 realm 加载 rubico，以避免重复获取。首先检查 `/CodeRunner.js`，了解当前的实现。查找 rubico 的加载方式，以及缓存可能发生的位置。目标是重构为使用共享副本，这可能需要了解 Realms 和模块结构。

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