Improve control on close reason

What's the intended usage pattern of the Reader and Writer context w.r.t. closing the connection from the server side?

It seems like the connection is closed automatically by the reader / writer when the context is cancelled. However, I don't have any way of impacting the status and reason for that close within the reader / writer.

Is the intention that the user of the reader / writer closes the connection with the status and reason they want and let the writer / reader return?

Another option could be that this package would support influencing the close status and reason via an error provided as context cancellation cause.

WDYT?

首先追踪 Reader 和 Writer 如何处理上下文取消，以及调用方目前如何关闭服务器端连接。将提议的 cancellation cause 方法与显式关闭连接进行比较，然后在确定两条路径的测试之前，定义预期的 close status 和 reason 行为。