feat: sample recent business events

internal/storage/mysql/operational_metrics_integration_test.go

@@ -60,6 +60,9 @@ func TestIntegrationOperationalSnapshot(t *testing.T) {
 	if got := snapshot.TaskStates["WAITING"]; got < 1 {
 		t.Fatalf("waiting task was not observed: %#v", snapshot.TaskStates)
 	}
+	if got := snapshot.RecentEvents["task.accepted"]; got < 1 {
+		t.Fatalf("accepted event was not observed: %#v", snapshot.RecentEvents)
+	}
 	if snapshot.TaskOldestAgeSeconds < 0 || snapshot.DeliveryOldestAgeSeconds < 0 || snapshot.WorkflowOldestAgeSeconds < 0 {
 		t.Fatalf("negative age in snapshot: %#v", snapshot)
 	}