Function check_remaining_closure 

pub fn check_remaining_closure(
    request: &ClosureCheckedEnvelope,
    accounting: ClosureAccounting,
    delivered_marker_awaiting_ack: bool,
    delta_cycles: u64,
    required_capacity: RequiredCapacityPlan,
) -> RemainingClosureDecision

Applies the remaining closure order: delivered marker, churn, then capacity.

Entries precede bytes and equality passes. A delivered-marker refusal uses delta_cycles=0; churn and capacity serialize the exact proposed charge.