[BUG] Interrupt (CTRL+C) claude process can break the install during auto-update

Environment

• Platform (select one):
• [x] Anthropic API
• Claude CLI version: (lost my state, so i can't check -- was one version before v1.0.9)
• Operating System: macOS 15.5
• Terminal: Terminal

Bug Description

I opened claude, realized i was in the wrong directory and hit ctrl+c to close and open up a new session, however the auto updator was presumably running in the background (Auto-updating to v1.0.9… was on the screen). This killed claude, but then broke my environment and claude binary was no longer available.

I had to npm i -g @anthropic-ai/claude-code to re-install.

Steps to Reproduce

1. run claude on a version that will try and auto-update
2. press ctrl+c a few times and interrupt at the right time (not sure when that is)
3. try and run claude again

Expected Behavior

Claude auto-updator should be safe / not self-break

Actual Behavior

claude uninstalled itself.