[BUG] Unicode box-drawing characters Γò¡ΓöÇΓöÇΓöÇΓ

Environment

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Anthropic API
AWS Bedrock
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Claude CLI version: 1.0.60 (Claude Code)
Operating System: Windows 11 (running in WSL)
Terminal: WSL (Windows Subsystem for Linux)

Bug Description
Unicode box-drawing characters in Claude Code's welcome interface are not rendering correctly, displaying as garbled text (Γò¡ΓöÇΓöÇΓöÇ etc.) instead of proper bordered boxes.
Steps to Reproduce

Open WSL terminal on Windows
Navigate to project directory
Run claude command to launch Claude Code
Observe the welcome screen display

Expected Behavior
The welcome screen should display clean bordered boxes with proper Unicode box-drawing characters forming a neat interface layout.
Actual Behavior
The interface displays garbled characters (Γò¡ΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓöÇΓò«) instead of box borders, making the interface difficult to read and unprofessional looking.
Additional Context

This appears to be a terminal encoding/font issue specific to WSL environments
This may affect other users running Claude Code in WSL or terminals with limited Unicode support