Docs Request: Add link to default config

If one runs copyparty without any config file, it just works. That's amazing! This setup would be a great template for config files.

Especially if the config file is nothing but a bunch of lines that could all be deleted (as they are the default behavior). It would show us every assumption, and give us an iterative way to progress.

找到 copyparty 定义其默认配置的位置，可能是在 config.py 或 defaults.py 之类的模块中。任务是在文档中添加指向此默认配置的链接，可能是在 README.md 或 docs/ 文件夹中。检查现有文档，找到讨论配置的位置，并在那里插入引用。通过在没有配置文件的情况下运行服务器进行验证，以确认其运行方式如描述所述。

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