VS Code Extension: command 'claude-vscode.editor.openLast' not found when clicking Extension UI button

Bug Description

Clicking buttons on the Claude Code VS Code Extension UI results in the error:

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

Commands work fine via Command Palette (Ctrl+Shift+P → Claude: ...), but the Extension panel buttons fail with this error.

Steps to Reproduce

1. Install Claude Code VS Code Extension (v2.1.53)
2. Open VS Code
3. Click on the Claude Code extension panel/button in the sidebar
4. Click any button on the Extension UI
5. Error appears: command 'claude-vscode.editor.openLast' not found

Expected Behavior

Clicking the button should open the last Claude conversation in the editor.

Actual Behavior

Error: command 'claude-vscode.editor.openLast' not found

Environment

• VS Code version: 1.109.5 (x64)
• Extension version: 2.1.53
• Claude CLI version: 2.1.53
• OS: Windows 11 Pro 10.0.26100

Troubleshooting Attempted

• Uninstalled and reinstalled the extension
• Reloaded VS Code window (Developer: Reload Window)
• Commands work via Command Palette but not via Extension UI buttons
• Extension appears in Running Extensions list

Notes

• The commands registered by the extension are accessible through the Command Palette, suggesting the extension activates partially but the UI buttons reference commands that are not properly registered or the activation event for those commands is not triggered.