Add checksum for pushdata/fetchdata

[Besroy]

From SM-long-running-test side, we encountered failures during the data read_verify process on two separate occasions:
Hash Mismatch: The issue occurred once where one follower experienced a hash mismatch.
Invalid Header: Another instance where a different follower encountered an invalid header.
Additional Details: For more comprehensive information and context regarding these failures, please refer to the documentation provided in the following link: Google Docs

[xiaoxichen]

quick fix , add length check in #586

Team discussed and decide to add checksum into the pushdata/fetchdata.
better to make it a configuration so that we can quantify the overhead in performance testing.