tmpclaude-*-cwd temp files not cleaned up after shell operations

Description

Temporary working directory files (tmpclaude-XXXX-cwd) are being created during shell command execution but are not being cleaned up afterward. These files accumulate over time across sessions.

Environment

• Claude Code VSCode Extension
• Windows 11
• Node.js v22.12.0

Steps to Reproduce

1. Use Claude Code in VSCode
2. Run multiple shell commands or background tasks
3. Check the project root directory

Expected Behavior

Temporary tmpclaude-*-cwd files should be automatically deleted after shell operations complete.

Actual Behavior

Files persist and accumulate. In one session, 32+ temp files accumulated:

tmpclaude-1e74-cwd
tmpclaude-2aa7-cwd
tmpclaude-2d6d-cwd
... (32 total)

Workaround

Added tmpclaude-*-cwd to .gitignore to prevent them from cluttering source control, but they still accumulate on disk.

Suggested Fix

Implement cleanup logic when:

• Shell command completes
• Session ends
• Extension deactivates