Function resolve_argument 

pub fn resolve_argument(
    proposer_instances: &[SchemeInstance],
    responder_instances: &[SchemeInstance],
    registry: &CatalogRegistry,
) -> ArgumentOutcome

Resolve an argument between proposer and responder scheme instances.

Builds an ASPIC+ StructuredSystem, adds all scheme instances, sets preference ordering based on scheme strength, computes preferred extensions, and determines which side’s conclusions survive.