[BUG] Session name lost from status line when exiting plan mode

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 a session is renamed (via /name), the custom name correctly appears in the status line. However, when transitioning from plan mode to accept/implementation mode, the
session name is lost.

What Should Happen?

Expected: Custom session name persists across the mode transition.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce:

1. Start a Claude Code session
2. Rename it with /rename "Custom Session Name"
3. Verify the custom name appears in the status line
4. Enter plan mode
5. Exit plan mode (approve the plan)
6. Session name in the status line lost

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.58.

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_