Implement HOST_UDF aggregation for reduction and groupby

[ttnghia]

This implements HOST_UDF aggregation, allowing to execute a host-side user-defined function (UDF) through libcudf aggregation framework.

• A host-side function can be an arbitrarily independent function running on the host machine. It may or may not call other device kernels depending on its implementation.
• Such user-defined function needs to follow the libcudf provided interface (cudf::host_udf_base). The interface provides the ability to fully interact with libcudf aggregation framework.
• Since it is implemented on the user application side, it has a very high degree of freedom to perform arbitrary operations to satisfy the user's need.

Closes #16633.

---

Usage

1. Define a functor deriving from cudf::host_udf_base and implement the required virtual functions declared in that base struct. For example:

struct my_aggregation : cudf::host_udf_base {
   ...
};

2. Create an instance of libcudf HOST_UDF aggregation which is constructed from an instance of the functor defined above. For example:

auto agg = cudf::make_host_udf_aggregation<cudf::groupby_aggregation>(
    std::make_unique<my_aggregation>());

3. Perform aggregation operation on the created instance.

[res-life]

Append HOST_UDF to the tail? then do not touch other aggregation values.

[ttnghia]

Unfortunately HOST_UDF is classified as "UDF" which should be grouped together with other UDF kinds. That's why I have to insert it in the middle.

[PointKernel]

The majority of the complexity in host_udf_base arises from its handling of both reduction and groupby operations. I mainly went through examples and tests and found this feature quite powerful overall. However, the design supporting both reduction and groupby could use some refinement. For now, I recommend focusing exclusively on groupby in the current work, which will help define the simplest possible interface for this new aggregation. Once that's established, we can extend the feature to include reduction. This approach will also help refine the scope of the PR, making it easier to review. @ttnghia What do you think?

[PointKernel]

A larger scope of changes is required since the given stream and mr need to be used for all the factories like make_lists_column, etc.

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[ttnghia]

This will be closed and replaced by multiple smaller PRs for easier review:

• Implement HOST_UDF aggregation for groupby #17592
• TBA

[mythrocks]

We don't intend for this change to be checked in, right?

[ttnghia]

Oh this was temporarily modified for local tests, and should be reverted now in the new PR.