[BUG] Claude Code freezes on "continue chat" in projects with many session files (regression in 2.1.30)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When attempting to continue/resume a chat in a project directory that has a large number of session files, Claude Code freezes completely. The UI becomes unresponsive - can't type or interact at all. Starting a new chat in the same directory works fine.

What Should Happen?

Claude Code should load the session list and allow continuing previous conversations, regardless of how many historical session files exist in the project.

Error Messages/Logs

No error messages - the application simply freezes/hangs indefinitely.

Steps to Reproduce

1. Have a project directory with 800+ conversation history files (.jsonl files in ~/.claude/projects/<project-dir>/)
2. Run claude in that project directory
3. Attempt to continue a previous chat (not start new)
4. Application freezes - no input possible

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.29

Claude Code Version

2.1.30 and later (tested up to 2.1.34)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

• Project has 827 .jsonl session files
• sessions-index.json is 34KB with ~579 entries
• New chats work fine - only "continue" freezes
• Downgrading to 2.1.29 resolves the issue completely
• Regression bisected: 2.1.29 works, 2.1.30 breaks