[Bug] PowerShell autocomplete crash: RuntimeError on arrow key navigation

Bug Description
/bug In Windows PowerShell, when typing "/" to access slash commands, the autocomplete menu appears briefly, but using arrow keys (or Tab) to navigate causes a crash with the error "RuntimeError: memory access out of bounds". This immediately exits the session.

Version: 2.0.70
OS: Windows (likely 10 or 11)
Terminal: PowerShell
Reproduction steps:

1. Start a new session with "claude"
2. Type "/"
3. Try to use arrow keys to select from the menu
4. Session crashes with the above error

Typing full commands like "/help" directly (without navigation) works as a workaround. Changing to Git Bash or Windows Terminal may avoid the issue, but PowerShell is commonly used.

This seems related to terminal input handling on Windows, possibly similar to known issues with key navigation in lists (e.g., resume sessions).

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.0.70
• Feedback ID: 8aed2588-9c60-42f0-90c8-28842a68ef4f

Errors

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