[BUG] /export command records wrong model version in output file header

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 using /export in a session running Claude Sonnet 4.6, the output file header records the model as Sonnet 4.5 instead of Sonnet 4.6.

What Should Happen?

The exported file header should record the correct model version that was actually used in the session (Sonnet 4.6).

Error Messages/Logs

<!-- Paste the relevant portion of the exported file header here -->

Steps to Reproduce

1. Start a Claude Code session using Sonnet 4.6
2. Run /export
3. Open the exported file and check the header
4. The model version in the header shows Sonnet 4.5 instead of Sonnet 4.6

Claude Model

Sonnet (Sonnet 4.6)

Is this a regression?

I don't know

Last Working Version

<!-- If regression, which version last worked? -->

Claude Code Version

2.1.116 (Claude Code)

Platform

AWS Bedrock

Operating System

Ubuntu/Debian Linux

Terminal/Shell

WSL

Additional Information