Copilot dumps output into prose instead of tool call etc.

### Short summary

App fails to make tool calls, and instead dumps output into the chat window

### Affected version or release

v0.2.34

### Installation context

app installed on my windows surface laptop

### What happened?

Instead of making the actual code change, it just dumped the content into chat output:

I was using interactive mode, claude opus 4.8 1M moduel, high reasoning, in a worktree session. using latest build at time of this issue open.

### Steps to reproduce

_No response_

### Expected behavior

_No response_

### Additional context

_No response_

未提及任何文件、测试或入口点。首先在交互模式下，使用所述的 Windows、worktree、模型和推理设置重现故障；将聊天输出与预期的工具调用行为进行比较。当应用程序执行工具调用并应用请求的代码更改时，即表示完成。

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