Function create_routed_model_provider_with_options 

pub fn create_routed_model_provider_with_options(
    config: &Config,
    primary_name: &str,
    api_key: Option<&str>,
    api_url: Option<&str>,
    reliability: &ReliabilityConfig,
    model_routes: &[ModelRouteConfig],
    default_model: &str,
    options: &ModelProviderRuntimeOptions,
) -> Result<Box<dyn ModelProvider>, Error>

Build a router fronted by primary_name plus one provider per unique model_routes entry. Each dotted <family>.<alias> name resolves through the typed [model_providers.<family>.<alias>] config (endpoint URI, Azure resource, Gemini OAuth, etc.); bare family names use family defaults.