Added Redis DIGEST command support for connection and template layer.

[Dgramada]

This PR adds support for the new Redis DIGEST command, available since Redis 8.4.0. The DIGEST command returns the XXH3 hash digest of a string value stored at a key, represented as a 16-character hexadecimal string.

The hash digest can be used for efficient comparison operations without needing to compare full string content. It integrates with Redis's SET command options (IFDEQ/IFDNE) and DELEX command for conditional operations based on value digests.

The PR adds methods for both reactive and synchronous template and connection layers.

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