[BUG] Cmd+T / Ctrl+T keyboard shortcut for new chat is not working

Describe the bug The keyboard shortcut Cmd+T (macOS) / Ctrl+T (Windows/Linux) for starting a new chat in Goose Desktop is not working. Users have to manually click the "New Chat" button every time they want to start a new session.

To Reproduce Steps to reproduce the behavior:

1. Open Goose Desktop
2. Start a conversation
3. Press Cmd+T (macOS) or Ctrl+T (Windows/Linux)
4. Nothing happens — the app does not navigate to the Home screen to start a new chat

Expected behavior Pressing Cmd+T / Ctrl+T should take the user to the Home tab, allowing them to start a new chat session (same behavior as clicking the "New Chat" button).

Environment

• Goose Desktop (all platforms affected)
• Previously implemented in PR #4541 / Issue #4535

Additional context

• This feature was previously added via PR #4541 ("Added CMD+T keyboard shortcut that takes you to the Home tab")
• The original feature request was Issue #4535
• The shortcut appears to have regressed / stopped working in recent builds
• The only workaround is to manually click the "New Chat" button