enum type for models

[AryaanSheth]

Create an enum type for all available models under GroqCloud

[AryaanSheth]

The list of models that Groq uses can be pulled via an API request. It might be easier to use that to check whether a request has a valid model. Not sure how much of an impact this would have on latency or cost.

[AryaanSheth]

Instead of an enum object, Groq handles wrong LLM inputs. Instead a command for getting all the LLMs available on Groq will be made and it is up to the consumer to create the logic should they need it.