Apache Pinot

I've been trying to add some new transform functions for use during ingestion, and it goes via `FunctionEvaluator`, which only supports `GroovyFunctionEvaluator` and `InbuiltFunctionEvaluator`  is this intentional? and is my best bet to add things I want to the `FunctionRegistry` via `@ScalarFunction`  annotations so they show up in `InbuiltFunctionEvaluator`?

I was hoping there would be a way to use a `TransformFunction` implementation so I can deal with different input types

You can drop your scalar function impl into plug-in dir and it should be picked up. TransformFunction (unlike scalar), is at block level and not row level

I just tested taking an `Object` and I can match on that and it seems to work

It might have an issue with v2 engine which needs to be strongly typed cc: <@UK6JD1E85> 

luckily I only want it in `transformConfigs` so I'm not sure that matters

<https://github.com/apache/pinot/pull/10347> for context I'm doing this

in terms of v2 usage this looks fine to me. left a few comments on the PR