fix(task): attribute async task usage log to the initiating node (#5684)

Async task usage logs (LogQuotaData node dimension) were recorded
under whichever node happened to poll the task to completion, not the
node that submitted it. For token/adaptor-billed video tasks the
pre-deduction is often 0, so the entire quota landed on the last
polling node.

Snapshot common.NodeName into TaskPrivateData at submit time and use
it when writing the settlement consume log; fall back to the current
node when empty so existing tasks stay compatible.

service/task_billing.go

@@ -241,6 +241,7 @@ func RecalculateTaskQuota(ctx context.Context, task *model.Task, actualQuota int
 		TokenId:   task.PrivateData.TokenId,
 		Group:     task.Group,
 		Other:     other,
+		NodeName:  task.PrivateData.NodeName,
 	})
 }