Starting to add Groq as a provider (#131)

.changeset/pink-terms-cheer.md

helpers/env-variables.ts

helpers/providers/groq.ts

helpers/providers/index.ts

helpers/types.ts

...ypes/streaming/express/src/controllers/engine/settings.ts

templates/types/streaming/fastapi/app/settings.py

...es/types/streaming/nextjs/app/api/chat/engine/settings.ts