[Bug] Claude Code exits silently without error logging on Windows PowerShell

Bug Description
Claude Code 2.1.121 on Windows 11, PowerShell 7.6.1, Node 22.16.0. Sessions started with claude exit silently within seconds — no error message, no debug log written, no Windows event log entry. claude --debug initially worked but now also fails. Non-deterministic: same command works in some tabs, not others; tabs that reach a working state tend to stay working until closed. Already tried: full reinstall, npm cache clean, removed .mcp.json, removed PowerShell aliases (used functions), PS 5.1 and PS 7, raised NODE_OPTIONS to 8GB heap, restored .claude.json from backup, tried from project folder and home folder. None resolved it. Spent ~half a day diagnosing with help from Claude in chat

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.1.121
• Feedback ID: aaff5437-e7ac-433a-9c5b-16e87e76647b

Errors

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