fix(operator): 每次运行首次就绪后留 3 分钟到达窗口再开始空服计时，停服或重启时清掉旧计时

internal/operator/export_test.go

@@ -7,3 +7,7 @@ func (r *Reconciler) ProbeMissesTracked() int {
 	defer r.probeMu.Unlock()
 	return len(r.probeFailures)
 }
+
+// ArrivalWindow is how long after a run's first ready probe a zero tally starts no
+// idle countdown.
+const ArrivalWindow = arrivalWindow