Fix Docker Compose models attribute and tests

[doringeman]

• Update the Docker Compose files. See https://docs.docker.com/ai/compose/models-and-compose/#service-model-binding.
• Replace string matching with jq validation to properly check for non-empty JSON responses with required keys ('response' and 'model').
  • i.e., $RESPONSE can be "Failed to get response from LLM" and $MODEL_INFO can be {"model":""}

Requires compose-spec/compose-go#824.

LE: Fixed: docker/compose@49b1c1e.