[BUG] Claude Code hangs when running `nmcli`

### 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?

Claude code hangs when connecting to VPN using `nmcli` on Linux. Example:

```
❯ Can you try to connect to VPN with "nmcli connection up my-vpn-connection" ?

I'll try bringing up that VPN connection.

● Bringing up rezdy-dev VPN connection · 60s
⎿ $ nmcli connection up my-vpn-connection 2>&1
```

Note that VPN connects within 5-10 seconds. However Claude doesn't seem to notice that and just keeps waiting...

I have confirmed `nmcli` itself does not hang as i'm able to use it normally.

### What Should Happen?

Claude should notice the VPN is connected, then continue on...

### Error Messages/Logs

```shell
See chat log above
```

### Steps to Reproduce

In Claude Code, ask Claude to connect to a VPN with `nmlcli`

```
nmcli connection up my-vpn-connection
```

### Claude Model

Opus

### Is this a regression?

I don't know

### Last Working Version

_No response_

### Claude Code Version

2.1.272 (Claude Code)

### Platform

Anthropic API

### Operating System

Other Linux

### Terminal/Shell

Other

### Additional Information

_No response_