feat(duo_workflow): Add http response to proto

What does this merge request do and why?

Adds HttpResponse and PlainTextResponse fields to ActionResponse messages. This MR only updates proto file and generated files.

This is in order to handle errors related to json parsing when http status is non-success.

Next steps are

• using these new fields in the Executor.
• read in AI Gateway from these new fields
• Cleanup usage of response
• Reserve and cleanup response from proto buffers.

Relates to: #951 (closed)

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

Merge request checklist

• Tests added for new functionality. If not, please raise an issue to follow up.
• Documentation added/updated, if needed.