[BUG] Shell snapshots export empty PATH on Windows (Git Bash), breaking command execution

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?

Description

On Windows with Git Bash, Claude Code generates shell snapshots that explicitly set PATH='', causing all subsequent Bash commands to fail with exit code 127 (command not found).

## Environment

• OS: Windows 10/11
• Shell: Git Bash (MINGW64)
• Claude Code Version: Latest
• Terminal: Tabby / PowerShell (launching Claude Code)

## Steps to Reproduce

1. Launch Claude Code on Windows
2. Execute any Bash command (e.g., which node, ls, etc.)
3. Command fails with exit code 127

## Root Cause

The generated snapshot files in ~/.claude/shell-snapshots/ contain:

```bash
# Line 85
export PATH=''

This explicitly clears the PATH variable. However, ORIGINAL_PATH environment variable correctly preserves the full system PATH.

Evidence

$ echo $PATH
# (empty)

$ echo $ORIGINAL_PATH
/mingw64/bin:/usr/bin:/c/Users/username/bin:...

Snapshot file content (last line):
export PATH=''

Expected Behavior

The snapshot should either:

1. Not override PATH at all
2. Use export PATH="$ORIGINAL_PATH" if PATH needs to be set
3. Preserve the actual PATH value from the shell environment

Workaround

Manually edit snapshot files to replace export PATH='' with export PATH="$ORIGINAL_PATH", or prefix every command with export PATH="$ORIGINAL_PATH" &&.

Additional Context

• Deleting snapshots and restarting Claude Code regenerates the same broken snapshots
• The issue persists across sessions
• Only affects Bash tool; other tools work normally

What Should Happen?

On Windows with Git Bash, Claude Code generates shell snapshots that explicitly set PATH='', causing all subsequent Bash commands to fail with exit code 127 (command not found).

Error Messages/Logs

Steps to Reproduce

1. Launch Claude Code on Windows
2. Execute any Bash command (e.g., which node, ls, etc.)
3. Command fails with exit code 127

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.75

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Additional Context

• Deleting snapshots and restarting Claude Code regenerates the same broken snapshots
• The issue persists across sessions
• Only affects Bash tool; other tools work normally