[BUG] Files corrupted to same-size null bytes after Edit tool operations, not reproducible in isolation

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?

Files corrupted to same-size null bytes after Edit tool operations, not reproducible in isolation

What Should Happen?

OS: Windows 11 Pro
Symptom: PostToolUse:Edit hook überschreibt bearbeitete Datei mit Null-Bytes (gleiche Dateigröße)
Hook-Ausgabe: "Z:\...\file is now visible in the Launch preview panel"
Reproduzierbar: ja, bei jedem Edit-Aufruf im Projekt

Error Messages/Logs

Files corrupted to same-size null bytes after Edit tool operations, not reproducible in isolation

Steps to Reproduce

Files corrupted to same-size null bytes after Edit tool operations, not reproducible in isolation

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.8555.1

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_