Disable thinking in LLMs so prompt expansion will work properly with thinking models

[shanedk]

This is my first ever PR, so be gentle! 😊

Summary

A bug fix to disable thinking on text LLM models so prompt expansion will work properly with thinking models.

Related Issues / Discussions

Closes #9379

QA Instructions

1. Try a thinking model. I was using Goekdeniz-Guelmez/Josiefied-Qwen3-1.7B-abliterated-v1
2. Type in a prompt
3. Use it to expand a prompt
4. Notice that you just get thinking tokens, no prompt
5. Apply this change
6. Try it again
7. Notice that you get a nicely expanded prompt now

Merge Plan

This is just adding an extra parameter, so I'm unaware of any such issues.

Checklist

• The PR has a short but descriptive title, suitable for a changelog
• Tests added / updated (if applicable)
• ❗Changes to a redux slice have a corresponding migration
• Documentation added / updated (if applicable)
• Updated What's New copy (if doing a release after this PR)