fix: change log level from info to error when reinitializing corrupted KeyMap

feat: implement 500 error response handling in server and client socket service

make mapdb as api so test cases can run

refactor: simplify SharedKeyMap usage by abstracting direct HTreeMap access

refactor: replace KryoSerializer with ForySerializer for all serialization operations.

Remove explicit `appender.sync()` call from ReplicationQueue's data writing process. Allow the OS to flush the data to file so that writes are faster.

refactor: simplify map value retrieval by using direct get() method instead of getUsing() to prevent same value beign returned

Refactor: Improve DB response status code handling by explicitly managing 400 and 503 statuses and refining retry logic.

fix: disable Kryo object reference handling in `KryoSerializer` configuration.

refactor: update import path for getPort utility in start and stop commands

feat: make HARD_LIMIT configurable via system property with a default value.

multi search with excluded keys test case

thread counts, but can still be set from system prop

speed up exclusion

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