How to ensure each event is delivered "exactly once"?

eventmesh-store was implemented based on RocketMQ by default as described, does it support delivering each event "exactly once"? If so, How to do that ?

Start with the eventmesh-store implementation and its default RocketMQ-based behavior. Determine whether exactly-once delivery is supported, what configuration or usage steps it requires, and what limitations apply. Done means the repository documentation clearly answers the question and describes the supported delivery semantics.

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