/ask frequently returns no result

### Describe the bug

Running the /ask command often fails to return any response. The command appears to execute but no output/result is produced, with no error message shonw.

### Affected version

1.0.75

### Steps to reproduce the behavior

1. Start a Copilot CLI session
2. Run /ask
3. Observe: no result is returned (not always)

### Expected behavior

/ask should reliably return an answer to the given question.

### Additional context

_No response_

启动一个 Copilot CLI 会话，并使用报告的版本 1.0.75 反复运行 /ask 命令，以复现间歇性缺少响应的问题。跟踪 /ask 命令的响应处理，并记录其在没有输出或错误的情况下完成的情形。当 /ask 能够可靠地返回该问题的答案，并且有一个覆盖无结果情况的回归测试时，即视为完成。

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