[BUG] OSC 0 / Window title no longer reports task display, just outputs "Claude Code"

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?

I love this thing, you can hook it up in vscode and see summaries of your conversations in a list.

Expected: Window title changes when using claude code.
Actual: Window title remains "Claude Code" in all sessions.

<img width="109" height="38" alt="Image" src="https://github.com/user-attachments/assets/6d2afd6f-84e2-4842-9edc-475ecb2b8d9a" />

What Should Happen?

Please restore previous behavior. I think it went out with the Opus 1M release.

Error Messages/Logs

Steps to Reproduce

Run claude
Observe Window title in terminal application or use tmux to see.
Observe:

<img width="109" height="38" alt="Image" src="https://github.com/user-attachments/assets/af85cd75-5241-46c6-8803-94609a106b32" />

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.74 idk

Claude Code Version

2.1.76

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Other

Additional Information

<3