[C++][Python] Non decomposable aggregation UDF (Hash version)

[icexelloss]

Describe the enhancement requested

In #35515,

I have implemented a Scalar version of the non decomposable UDF (Scalar as in SCALAR_AGGREGATE). I would like to support the Hash version of it (Hash as in HASH_AGGREGATE)

Component(s)

C++

[icexelloss]

take