/resume command becomes unresponsive after window switch with NO_FLICKER enabled

Description

When \CLAUDE_CODE_NO_FLICKER=1\ is set, the \/resume\ command interface becomes unresponsive after switching to another window and back.

Steps to Reproduce

1. Set \CLAUDE_CODE_NO_FLICKER=1\ in environment variables or settings.json
2. Launch Claude Code
3. Type \/resume\ and press Enter
4. Press Up arrow to enter search/filter mode
5. Switch to another application window (Alt+Tab or click taskbar)
6. Switch back to Claude Code window
7. Try to exit the \/resume\ interface (Escape, Ctrl+C, etc.)

Expected Behavior

• Should be able to exit the \/resume\ interface with Escape or other standard keys
• Input should remain responsive after window focus changes

Actual Behavior

• Cannot exit the \/resume\ interface
• Keyboard input is not processed
• Terminal appears frozen/blocked

Environment

• OS: Windows 11 Home China (10.0.26200)
• Shell: PowerShell 5.1
• Claude Code version: Latest
• Terminal: Windows Terminal

Workaround

• Remove \CLAUDE_CODE_NO_FLICKER=1\ from settings
• Use \Ctrl+C\ to force interrupt (may not always work)
• Close and restart Claude Code

Related Configuration

\\\json
{
env: {
CLAUDE_CODE_NO_FLICKER: 1
}
}
\\\

Additional Notes

This bug appears to be related to focus state management in the TUI rendering when NO_FLICKER mode is enabled. The issue specifically occurs when:

1. The /resume command is in search/filter mode
2. The window loses focus
3. The window regains focus

The NO_FLICKER setting may be affecting the event loop or focus recovery logic.