HACEP Refactor DefaultKafkaConsumer

Try to uniform leader/replica flow:

• If I'm the leader it invokes `defaultProcessAsLeader` -> `processLeader` -> `process/processWithSnapshot`
• If I'm a replica it invokes `defaultProcessAsAReplica` -> `consumeEventsFromBufferAsAReplica` -> `processEventsAsAReplica` -> `process`

Try to remove most/all boolean and use proper method parameter

Verify defaultProcessAsAReplica else branch. This should never happen because if leader sent a message about process a specific event, it should be available