Proposal: Add `AbortSignal.timeout()` shorthand to "Fetch: Abort" article

Description

The "Fetch: Abort" article excellently explains the mechanics of AbortController and demonstrates a manual timeout using

setTimeout(() => controller.abort(), 1000)

Since aborting fetches due to time constraints is a very common use case, it would be highly beneficial for learners to also see the modern AbortSignal.timeout() method.

Proposal

I propose adding a short subsection titled ### AbortSignal.timeout() immediately following the try..catch block of the manual timeout example. This section will demonstrate the shorthand syntax and note the important distinction that it throws a TimeoutError rather than an AbortError.

打开 5-network/04-fetch-abort/article.md 并阅读手动超时示例，尤其是 try..catch 块。紧接着在其后添加提议的 AbortSignal.timeout() 小节，展示简写形式并解释 TimeoutError 与 AbortError 之间的区别。当文章清晰涵盖这两种超时方式时，即表示完成。