[BUG] VS Code extension: opening conversations repeatedly creates empty "Untitled" sessions

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?

Each click adds an empty "Untitled" session.

What Should Happen?

No new session until a message is sent, or the existing empty session is reused.

Error Messages/Logs

Steps to Reproduce

1) Open the Claude Code panel. 2) Click open conversations several times. 3) Open the Local session list.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

NA

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Env: extension version, VS Code version, macOS version.

<img width="420" height="444" alt="Image" src="https://github.com/user-attachments/assets/b6d3b0ba-93ca-4b6e-9a20-fa59965648f1" />