clickhouse-keeper: real-time digest calculation and verification support added

Why it matters

This feature provides continuous verification of data consistency within clickhouse-keeper by calculating and verifying digests in real-time. It helps detect data corruption or inconsistencies promptly, improving reliability and trustworthiness of the system.

How to use it

The real-time digest calculation and verification feature is disabled by default. To enable it, you need to configure the clickhouse-keeper settings accordingly in its configuration file, activating the digest calculation and verification options.