Input box clips first 1-2 characters in Alacritty on Windows (works in Windows Terminal)

Environment

• Claude Code: v2.1.161
• OS: Windows 10 Pro (10.0.19045)
• Terminal: Alacritty
• Shell: PowerShell 7
• Font: EnvyCodeR Nerd Font Mono

Bug description

The input box at the bottom of the TUI clips the first 1-2 characters of typed text and the prompt indicator. The leftmost characters are hidden behind the left edge of the terminal.

Steps to reproduce

1. Open Alacritty on Windows with PowerShell 7
2. Launch claude
3. Send a couple of messages
4. Around the 3rd message, the input box starts clipping the leftmost 1-2 characters

Expected behavior

Full prompt indicator and input text are visible, matching the correct behavior in Windows Terminal.

Additional context

• Works correctly in Windows Terminal with identical shell and configuration
• Reproducible with and without psmux (terminal multiplexer)
• Setting the COLUMNS env var at launch delays the issue but does not prevent it — suggesting process.stdout.columns is re-read each render and returns a wrong/stale value via Alacritty's ConPTY interface on Windows

Screenshot

<img width="800" height="631" alt="Image" src="https://github.com/user-attachments/assets/3f89c7df-5639-4c61-a8aa-a37697a20aaf" />

<img width="1113" height="949" alt="Image" src="https://github.com/user-attachments/assets/f093b059-82df-4005-9019-64ef29b7546a" />