feat: introduce ack trackers to prevent batch message loss #1277
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Motivation
In the current implementation of messageID.Serialize(), the ackTracker information is not recorded. This causes an issue when the client uses DeserializeMessageID to restore the message ID. The Pulsar consumer will mistakenly acknowledge the message within the batch, causing other unacknowledged messages in the batch to be acknowledged as well. This results in message loss for the client.
Modifications
In the current consumer implementation, maintain the ackTrackers structure. When a trackingMessageID lacks an ackTracker, attempt to retrieve it from ackTrackers. Only remove the corresponding ackTracker from ackTrackers after all messages in the batch have been acknowledged.