Function select_rlm_model_with_env 

pub fn select_rlm_model_with_env(
    config: &RlmConfig,
    purpose: RlmModelPurpose,
    caller_model: &str,
    env_model: Option<&str>,
    _score: impl Fn(&str) -> Option<f64>,
) -> RlmModelChoice

Select an RLM model with an injected env value for deterministic tests.