Redis 8.8: Add XNACK support

[uglide]

Adds support for XNACK command introduced in Redis 8.8 redis/redis#14797

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Note

Medium Risk
Adds a new Redis Streams command across sync/async/reactive/coroutines APIs and updates command encoding/command-type plumbing; risk is mainly API surface expansion and correctness of argument serialization.

Overview
Adds client support for Redis 8.8 Streams negative acknowledgements via the new XNACK command.

Introduces the XNackMode keyword enum and wires xnack methods (single-id and varargs overloads) through the sync/async/reactive/cluster node-selection and Kotlin coroutines APIs, backed by new RedisCommandBuilder.xnack command construction and a new CommandType.XNACK.

Extends unit/integration test coverage to validate request encoding, argument validation, and basic Redis-side behavior (including multi-id and non-existent IDs) when XNACK is available.

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[jit-ci]

🛡️ Jit Security Scan Results

✅ No security findings were detected in this PR

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[a-TODO-rov]

#3728 (comment)
Actually, i will answer myself here. I think its important from now on to support overloads for varargs.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[a-TODO-rov]

Thanks @uglide
LGTM