[INTEGRATION] Add instructor to generate structured outputs from private APIs

[plaguss]

Is your feature request related to a problem? Please describe.
In #601 we added the possibility to generate structured outputs from llama-cpp, transformers and vllm using outlines. It would be nice to have instructor for the API integrations.

Describe the solution you'd like
Work with instructor in a similar way as we have with outlines.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.