[Windows] Persistent bun.exe terminal window with "Cannot read file System32" EPERM error

Description

When running Claude Code on Windows, a persistent terminal window spawns and remains open showing an error:

• Window title: C:\Users\QESG\.bun\bin\bun.exe
• Error message: error: Cannot read file "C:\Windows\System32\": EPERM

Behavior

• The terminal window spawns during any Claude Code operation (no specific trigger identified)
• Window persists - it does not flash/disappear like other reported window issues
• Only one window appears at a time (never 2+)
• If manually closed, it reappears at some point during the session
• Does not seem to affect Claude Code functionality otherwise

Screenshot

<img width="979" height="512" alt="Image" src="https://github.com/user-attachments/assets/2953e94b-0fcf-4000-9fce-48a0460a9b06" />
(Terminal window showing the EPERM error)

Environment

• OS: Windows 10 (MINGW64_NT-10.0-19045 3.5.4)
• Claude Code version: 2.1.31
• Bun version: 1.3.8
• Node version: v22.21.1
• Install method: native

Steps to Reproduce

1. Run Claude Code on Windows
2. Perform any operation (chat, tool execution, etc.)
3. At some point, the bun.exe terminal window appears with the EPERM error
4. Window stays open until manually closed
5. Eventually reappears

Expected Behavior

No external terminal window should spawn, or if a process needs to run, it should be hidden (windowsHide: true).

Additional Context

• Plugins enabled: context7, plugin-dev, ralph-wiggum, claude-hud
• Custom statusLine configured (uses Node, not Bun directly)
• No custom MCP servers configured

Related Issues

• #14828 - Console window flashing (different: flashing vs persistent)
• #19012 - Hook window flash (different: no error, just flash)
• #14242 - EPERM error (different: mkdir error, not System32 read)