Better handle sending recursive inventories

[Muqsit]

The NetworkStackLatencyPacket method isn't any better than delayed tasks as it has a high rate of failure for low-latency users. A more reliable method would be one that:

• Doesn't rely on client-side latency
• Doesn't rely on server-side delay (such as TaskScheduler::scheduleTask and PlayerNetwork::waitUntil)

Possible solution: Client sends ContainerClosePacket back after server sends one. Perhaps server could queue next InvMenu::send request until then.