Add Redis cluster mode support to RedisHook

[FrankYang0529]

Why

• Redis Cluster splits the keyspace into 16384 hash slots spread across masters. Any key-based command must reach the node owning that key's slot, otherwise the node answers MOVED instead of serving it.
• RedisHook only built a standalone redis.Redis client, which does not follow those redirects. So every key-based operation in this provider can fail, depending on where the key happens to hash.
  • RedisTaskHandler (remote logging) — lrange to read, rpush/ltrim/expire to write. Its key is derived from dag id, run id and task id, so each task instance's log targets a different node.
  • RedisKeySensor uses exists to watch key. The key can be dynamic string, so it can be on different nodes.

How

• Add a cluster connection extra. When set, get_conn() builds a redis.cluster.RedisCluster, which follows MOVED/ASK redirects.
• Add a startup_nodes extra to supply extra bootstrap nodes.

Verification

• uv run --project providers/redis pytest providers/redis/tests/unit/redis/hooks/test_redis.py -xvs
• breeze testing providers-integration-tests --db-reset --integration redis

• closes: Add support for Redis in Cluster Mode #10504

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Was generative AI tooling used to co-author this PR?

• Yes - Claude Code

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[Miretpl]

Could you also adjust the PR description in terms of why it is needed? Currently, we only know the difference between standalone Redis and cluster deployment and how it handles connections.

[FrankYang0529]

@Miretpl Thanks for the review. I addressed all comments and updated PR description.

[Miretpl]

Just small nit about exception messages and LGTM.