Atomic Maestro Sessions + Shutdown gate

Co-Authored-By: brekotis <93345790+brekotis@users.noreply.github.com>

src/maestro/me_startup.rs

@@ -585,6 +585,7 @@ pub(crate) async fn initialize_me_pool(
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::sync::atomic::{AtomicUsize, Ordering};
     use tokio::sync::Notify;
 
     struct DropSignal(Arc<Notify>);
@@ -615,4 +616,34 @@ mod tests {
             .await
             .unwrap();
     }
+
+    #[tokio::test]
+    async fn supervisor_restarts_exited_child_and_stops_with_runtime_scope() {
+        let scope = RuntimeTaskScope::new();
+        let starts = Arc::new(AtomicUsize::new(0));
+        let restarted = Arc::new(Notify::new());
+        let starts_task = starts.clone();
+        let restarted_task = restarted.clone();
+        scope.spawn(supervise_me_task("restart_test", move || {
+            let starts = starts_task.clone();
+            let restarted = restarted_task.clone();
+            async move {
+                if starts.fetch_add(1, Ordering::AcqRel) + 1 >= 3 {
+                    restarted.notify_one();
+                }
+            }
+        }));
+
+        tokio::time::timeout(Duration::from_secs(1), restarted.notified())
+            .await
+            .unwrap();
+        scope.stop().await;
+        let stopped_at = starts.load(Ordering::Acquire);
+        for _ in 0..100 {
+            tokio::task::yield_now().await;
+        }
+
+        assert!(stopped_at >= 3);
+        assert_eq!(starts.load(Ordering::Acquire), stopped_at);
+    }
 }