Write a producer class that batches messages before sending them to a network endpoint, given a maximum number of held messages and a maximum time any message may be held.

Write a producer class that accepts messages and sends them to a predefined network endpoint, but batches them instead of sending each one on arrival. The constructor takes (1) the maximum number of messages the producer may hold at any instant and (2) the maximum time any message may be held before it must be sent. Expose a public SendMessage(string) API. The instance is created by one process and may be shared.