[BUG] False "Update available" notification when already on latest version

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?

Claude Code v2.1.20 shows "Update available! Run: winget upgrade Anthropic.ClaudeCode" message, but the installed version is already the latest.

What Should Happen?

No update notification when already on the latest version.

Error Messages/Logs

Steps to Reproduce

1.Install Claude Code via winget install Anthropic.ClaudeCode
2.Run winget upgrade Anthropic.ClaudeCode - shows no updates available
3.Launch Claude Code - still shows "Update available" message

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.20

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_