[SPARK-52407][SQL] Add support for Theta Sketch

[cboumalh]

What changes were proposed in this pull request?

This PR's goal is to provide 7 new functions which utilize Theta Sketches.
The functions are:

theta_sketch_agg(sketch_col)
theta_union(sketch1, sketch2)
theta_union_agg(sketch_col)
theta_difference(sketch1, sketch2)
theta_intersection(sketch1, sketch2)
theta_intersection_agg(sketch_col)
theta_sketch_estimate(sketch)

Why are the changes needed?

Today, Spark supports HyperLogLog. HLL only supports the union set operation. Theta on the other hand allows us to find the difference and intersection between two sketches.

Does this PR introduce any user-facing change?

Yes, this PR introduces three new aggregate functions:

theta_sketch_agg
theta_intersection_agg
theta_union_agg

And four new scalar functions:

theta_sketch_estimate
theta_intersection
theta_difference
theta_union

How was this patch tested?

I've included some tests in ThetasketchesAggSuite test suite. I also tested it locally on my machine.

Was this patch authored or co-authored using generative AI tooling?

No

Jira

https://issues.apache.org/jira/browse/SPARK-52407

[cboumalh]

I know there is probably a lot missing in the PR before it's ready to merge. Please let me know!
@mkaravel @RyanBerti