Introduce HashBucketAssigner

[luoyuxia]

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• I searched in the issues and found nothing similar.

Description

Refer to java https://github.com/apache/fluss/blob/de2d9a042637386f9c8f59bddbff8a1a66853ca0/fluss-client/src/main/java/org/apache/fluss/client/write/HashBucketAssigner.java#L26
Please make sure the hash consist with java

Willingness to contribute

• I'm willing to submit a PR!

[leekeiabstraction]

@luoyuxia Can you assign this to me? Thank you!

[luoyuxia]

@leekeiabstraction Thank you!