Escape key fails to interrupt generation when system reminders trigger repeated responses

Description

When system reminders (e.g., task tracker notifications) trigger repeated tool calls and responses, pressing Escape fails to reliably interrupt Claude's generation. The user reported pressing Escape at least 20 times without success.

Steps to reproduce

1. Have background tasks running that generate system reminder notifications
2. Tell Claude to stop
3. System reminders about task status trigger new responses/tool calls despite the user saying "stop"
4. Press Escape repeatedly to try to interrupt — it does not work

Expected behavior

Pressing Escape should immediately cancel the current generation and prevent new tool calls from being initiated, regardless of incoming system reminders.

Actual behavior

Escape key presses are ignored or ineffective. The only apparent way to stop the loop is to kill the program entirely, which loses conversation context.

Environment

• Claude Code CLI
• macOS (Darwin 25.2.0)
• Shell: zsh