Create a condition for filtering by product value

Also spun off from #2842924: Add a product condition.

We'd want to offer all fields except entity keys, attributes, price fields. Question is how to handle configurable fields, a bundle selector that refreshes a field list, or a big field list that includes fields for all bundles? Should we even indicate which bundle a field belongs to?

Also, can/should we allow selecting product variation fields as well? Might make sense if we can pull of a select with two groups (Product and Product variation).