[BUG] Sandboxed warning only appears if project on .claude/projects/* doesnt exists

Preflight Checklist

• [x] I have searched existing issues 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?

When open a project initialized, and sandbox is active, the warning message of sandboxing bash command doesnt appears.

We understand this as a UX bug, sorry if is not well categorized

What Should Happen?

<img width="646" height="57" alt="Image" src="https://github.com/user-attachments/assets/6f4a9c9c-ffed-4a40-b59f-a32a7fdd7589" />

Show message on top when sandbox is active

Error Messages/Logs

Steps to Reproduce

1. open claude on a directory whitout claude.md
2. run /init
3. close claude code.
4. open claude again

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.148

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

This is an example, sandbox active but no warning shows:
<img width="786" height="211" alt="Image" src="https://github.com/user-attachments/assets/899b0ccd-14cb-424d-836a-11f79b02e1dc" />