[BUG] Activity Bar icon missing and commands broken in v2.1.136

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?

After updating to v2.1.136, the Activity Bar icon disappeared and
several commands stopped working:

• Activity Bar icon not visible (even with preferredLocation: "sidebar")
• Commands return "not found" errors (e.g., claude-vscode.sidebar.open)
• Claude Opus model missing from model selector (only Haiku visible)

Rolling back to v2.0.62 fixes all issues immediately.

What Should Happen?

The Activity Bar icon should be visible on the left sidebar,
and all extension commands should work normally.
Claude Opus model should be available in the model selector.

Error Messages/Logs

command 'claude-vscode.sidebar.open' not found
command 'claude-vscode.editor.openLast' not found

Steps to Reproduce

1. Install Claude Code v2.1.136 from VS Code marketplace
2. Open VS Code
3. Check Activity Bar (left sidebar) - icon is missing
4. Try Ctrl+Shift+P → "Claude Code: Open in Side Bar" - command not found
5. Check model selector in an existing Claude conversation - Opus missing

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.0.62

Claude Code Version

2.1.136

Platform

Other

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

• Issue appears immediately after updating from 2.0.62 to 2.1.136
• Rolling back to 2.0.62 fixes all issues instantly
• Tried clean reinstall and deleting extension folder - did not help
• preferredLocation setting set to "sidebar" but icon still doesn't appear
• Multiple users reporting same issue: #14193, #14317, #55266