Method replace_snapshots

core/src/subagent_task_tracker.rs:322–330

Replace the tracker's task snapshots with the given set. Cancellers are **not** restored (they are runtime-only channels tied to live child loops). After `replace_snapshots`, any task whose status was `Running` at checkpoint time will appear `Running` in the tracker but `cancel(task_id)` will return `false` because no canceller is registered — callers should normally checkpoint at a quiescent poin

(&self, snapshots: Vec<SubagentTaskSnapshot>)

    /// restore the materialized subagent view of a previously-saved
    /// session.
    pub async fn replace_snapshots(&self, snapshots: Vec<SubagentTaskSnapshot>) {
        let mut map = HashMap::with_capacity(snapshots.len());
        for snap in snapshots {
            map.insert(snap.task_id.clone(), snap);
        }
        *self.tasks.write().await = map;
        // Cancellers reference live tokens — invalidate the lot.
        self.cancellers.write().await.clear();
    }
}

fn now_ms() -> u64 {