Update FACTORY_SETUP.md with configuration for Qwen models

[claudio-silva]

Hi,
I missed this configuration when setting up my Factory CLI, so I did some searching to come up with the setup below.
I’m sharing it here, in case it saves someone else the same trouble when updating ~/.factory/config.json to use Qwen models.
Perhaps you can update FACTORY_SETUP.md with these, unless you already have a better configuration, of course.

    {
      "model_display_name": "Qwen3 Coder Plus",
      "model": "qwen3-coder-plus",
      "base_url": "http://localhost:8317/v1",
      "api_key": "dummy-not-used",
      "provider": "generic-chat-completion-api"
    },
    {
      "model_display_name": "Qwen3 Max",
      "model": "qwen3-max",
      "base_url": "http://localhost:8317/v1",
      "api_key": "dummy-not-used",
      "provider": "generic-chat-completion-api"
    },
    {
      "model_display_name": "Qwen Plus",
      "model": "qwen-plus",
      "base_url": "http://localhost:8317/v1",
      "api_key": "dummy-not-used",
      "provider": "generic-chat-completion-api"
    }

P.S. I don't know if max_tokens should be specified.