Add GitHub testing workflow

[pamelafox]

Purpose

Adds a simple workflow using GitHub Models to test that examples work

Also improves compatibity of reasoning example with gpt-oss

Does this introduce a breaking change?

[ ] Yes
[ ] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[X] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

How to Test

• Run the workflow