Function should_interrupt 

pub fn should_interrupt<S: State>(
    pending_tasks: &[PendingTask<S>],
    interrupt_before: &HashSet<String>,
    interrupt_after: &HashSet<String>,
    channel_versions: &HashMap<String, u64>,
    versions_seen_for_interrupt: &HashMap<String, u64>,
) -> Option<Vec<InterruptSignal>>

Check if execution should interrupt based on the current state

Two-step check:

1. Version gating: Only fire if any channel was updated since the last interrupt (comparing channel_versions against versions_seen_for_interrupt).
2. Node name check: Verify that a pending task targets a node listed in interrupt_before or interrupt_after.

The version gate prevents infinite interrupt loops after checkpoint restore when no state actually changed.

Arguments

• pending_tasks - Tasks scheduled for the next superstep
• interrupt_before - Nodes that should interrupt before execution
• interrupt_after - Nodes that should interrupt after execution
• channel_versions - Current field version map (channel -> version)
• versions_seen_for_interrupt - Last-seen channel versions at the time of the previous interrupt (flat map: channel -> single version)

Returns

Some(Vec<InterruptSignal>) if interruption is needed, None otherwise