Feature Request: Allow renaming Claude Code tab titles in VS Code extension

Feature Request

When using multiple Claude Code tabs/sessions in VS Code, it's difficult to distinguish between them. The tab titles show generic names like "/sc:brainstorm http://lo..." which are hard to identify.

Proposed Solution

Allow users to rename tab titles in the VS Code extension:

1. A built-in /rename <name> command that works in VS Code (currently returns "Unknown skill")
2. Right-click context menu on the tab to rename
3. VS Code command palette option ("Claude Code: Rename Session")

Current Behavior

• /rename returns "Unknown skill: rename" in VS Code extension
• Tab titles are auto-generated and not editable

This would greatly improve workflow for users running multiple parallel sessions.