[BUG] /web-setup slash command silently absent if Claude Code is run with CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=true

Preflight Checklist

• [x] I have searched existing issues and this has been incorrectly closed by @github-actions - see #40876.
• [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?

The onboarding instructions at https://claude.ai/code/onboarding advise running /web-setup in Claude Code. That command isn't available in the latest Claude Code version if it was run with CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=true.

<img width="667" height="482" alt="Image" src="https://github.com/user-attachments/assets/3a9fb297-39d0-4f45-a918-39d27ce11500" />

What Should Happen?

For better DX, CC should output that /web-setup requires traffic disabled by CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=true, and suggest re-running without the flag.

Also, the bot shouldn't close unsolved issues. This issue is mostly a duplicate of #40876, and presents a workaround for @Vladimir0770.

Error Messages/Logs

● Unknown command: /web-setup

Steps to Reproduce

1. Run CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=true claude
2. Type /web-setup

Claude Model

Irrelevant.

Is this a regression?

No, this never worked.

Claude Code Version

2.1.187

Platform

Claude Pro account.

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Konsole.