[BUG] terminal shows 'done working' on /btw question

### Preflight Checklist

- [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) and this hasn't been reported yet
- [x] This is a single bug report (please file separate reports for different bugs)
- [x] I am using the latest version of Claude Code

### What's Wrong?

windows terminal claude code shows like completed (green icon) near the title of the CMD when asked /btw question (even if /btw still not responded)

### What Should Happen?

should show the green (finished) icon only when /btw responded

### Error Messages/Logs

```shell

```

### Steps to Reproduce

1. ask /btw
2. look on icon

### Claude Model

None

### Is this a regression?

No, this never worked

### Last Working Version

_No response_

### Claude Code Version

2.1.241

### Platform

Anthropic API

### Operating System

Windows

### Terminal/Shell

Windows Terminal

### Additional Information

Start by reproducing the issue in Claude Code 2.1.241 on Windows Terminal: run /btw and observe when the terminal title icon changes. Trace the /btw entry point and the status indicator handling, then verify that the finished icon appears only after the /btw response is complete.

索引モデルが issue の本文から書いたものです。