[BUG] Backspace key repeat issue in WSL with Windows Terminal

Environment

• Platform (select one):
• [x] Anthropic API
• [ ] AWS Bedrock
• [ ] Google Vertex AI
• [ ] Other: <!-- specify -->
• Claude CLI version: 1.0.89
• Operating System: Windows 11
• Terminal: Windows Terminal

Bug Description

When using Claude Code in Windows Terminal (via WSL), if you press and hold the backspace key, rather than repeatedly deleting input characters, the cursor gets stuck and the border character from the right of the input box begins to creep to the left. If you then release the backspace key and start pressing it (rather than holding it), the border character steps back to the right one character at a time. This makes it very cumbersome to delete portions of text, as you have to explicitly press backspace over and over - you can't just hold it down. Easiest to show with a video:

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Steps to Reproduce

1. Setup Claude Code in WSL / Windows 11
2. Install https://apps.microsoft.com/detail/9n0dx20hk701?hl=en-US&gl=US
3. Enter at least 2 or 3 lines of text
4. Press and hold the backspace key