[Bug] claude update - multiple installations detected at same path after npmrc prefix change

Bug Description

It's the same path /Users/user/.local/bin/claude, but shows as multiple installations

Current version: 2.1.77
Checking for updates to latest version...

Warning: Multiple installations found

• npm-global at /Users/user/.local/bin/claude
• native at /Users/user/.local/bin/claude (currently running) - the path is the same. Seeing this error after changing ~/.npmrc prefix: prefix=/Users/user/.local for global npm packages

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.1.77
• Feedback ID: a17ecbdc-fcdc-44ac-b179-b4e731564954