Adapts ReqLLM to the Gut.Adapter contract.
This adapter requires the optional req_llm dependency. Applications that
use it must add req_llm to their dependencies:
{:req_llm, "~> 1.24"}Adapter options pass through to ReqLLM.generate_text/3. This adapter owns
the structured output option and uses strict validation with a temperature
of zero unless the adapter options override it.