Auto-update fails with ENOTEMPTY error on repeated attempts

Description

Claude Code auto-update consistently fails with npm ENOTEMPTY error when updating. The auto-updater tries to rename the existing directory but fails if a temp directory from a previous failed update exists.

Error

npm error code ENOTEMPTY
npm error syscall rename
npm error path ~/.nvm/versions/node/v20.19.5/lib/node_modules/@anthropic-ai/claude-code
npm error dest ~/.nvm/versions/node/v20.19.5/lib/node_modules/@anthropic-ai/.claude-code-XXXXX
npm error errno -39
npm error ENOTEMPTY: directory not empty, rename '...' -> '...'

Environment

• OS: Linux (WSL2)
• Node: v20.19.5 (via nvm)
• Claude Code: 2.1.2

Steps to Reproduce

1. Have Claude Code installed via npm
2. Auto-update triggers (or fails once)
3. Subsequent auto-updates fail with ENOTEMPTY

Workaround

rm -rf ~/.nvm/versions/node/v20.19.5/lib/node_modules/@anthropic-ai
npm i -g @anthropic-ai/claude-code

Suggested Fix

The auto-updater should clean up any existing .claude-code-* temp directories before attempting the rename operation.