[BUG] "Restart now" button does nothing when update is ready

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?

When an update is downloaded and the banner shows "Restart now"
to install the update, clicking the button does nothing. Clicked
multiple times but the app does not restart and update is not installed.

What Should Happen?

• App should quit and restart automatically
• Update should be installed after restart

Error Messages/Logs

**Expected Behavior:**
- App should quit and restart automatically
- Update should be installed after restart

**Actual Behavior:**
- Button click does nothing
- App stays open
- Update not installed
- User has to manually quit and reopen

Steps to Reproduce

1. See banner: "Update downloaded - A new version is ready to install"
2. Click "Restart now"
3. Nothing happens
4. Click again multiple times
5. Still nothing happens
6. App does not restart
7. Update is not installed

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.1.2321 (495628)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

<img width="722" height="339" alt="Image" src="https://github.com/user-attachments/assets/01c83d1d-486a-41f7-ac03-92962bc1e871" />