Function get_defined_objects 

pub fn get_defined_objects(
    defined: &str,
    sa: &SpellAbility,
    game: &GameState,
) -> (Vec<PlayerId>, Vec<CardId>, Vec<SpellAbility>)

Resolve a Defined$ expression to a combined list of the targeted GameObjects — cards + players + spell abilities. Mirrors Java AbilityUtils.getDefinedObjects(Card, String, CardTraitBase).

The three sub-resolvers are surfaced separately via their native Rust enums rather than a shared GameObject trait object, so this helper returns a tuple instead of Java’s FCollection<GameObject>.