[BUG] CRITICAL: Write tool creates files outside working directory on Windows

## 🚨 Critical Security Issue

Problem: Claude Code Write tool created files outside the designated working directory

Environment:

• OS: Windows 11
• Working Directory: C:\Users\[username]\Projects\MyRepo
• Shell: Git Bash (MINGW64)

What Happened:

• Claude was asked to create files in solutions/project-name/new-component/
• Instead created files in C:\c\Users\[username]\Projects\MyRepo\solutions\project-name\new-component\
• This created an unauthorized directory structure starting from C:\c\

Security Impact:

• Claude gained write access to system root directory (C:\)
• Could potentially overwrite system files or create unauthorized directories
• Violates expected sandbox restrictions

Root Cause Analysis:

• Appears to be Git Bash Unix-style path (/c/Users/...) being incorrectly translated to Windows filesystem
• Write tool may be interpreting absolute paths incorrectly on Windows

Reproduction Steps:

1. Use Claude Code on Windows with Git Bash environment
2. Ask Claude to create multiple files in a project subdirectory
3. Use Write tool with absolute path references
4. Observe files created in C:\c\... instead of intended location

Expected Behavior:

• All file operations should be restricted to working directory
• Should error if attempting to write outside sandbox
• Path resolution should be consistent with working directory context

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