feat(amazonq): add description field to Model class

[chungjac]

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Description

We want to display the model description.

This is needed in JB for it to be able to display (Not needed in VSC)

This is already returned from the backend, hence we just need to display it.

Checklist

• My code follows the code style of this project
• I have added tests to cover my changes
• A short description of the change has been added to the CHANGELOG if the change is customer-facing in the IDE.
• I have added metrics for my changes (if required)

License

I confirm that my contribution is made under the terms of the Apache 2.0 license.