refactor `RadixSortLSD` so that multiple sort configurations can be instantiated at the same time

[mhmerrill]

refactor RadixSortLSD so that multiple sort configurations can be instantiated at the same time. This will enable us to to support multiple sort configurations at the same time.

[mhmerrill]

from our discussions I think we are going to:

• add a new Msg function to the server to generate RadixSortLSDPlans calling makeRadixSortLSDPlan() and caching the plans in a map.
• have all places which use the sort call chooseRadixSortLSDPlan() with the primary argument to this function being the input array size.

This will allow us to encapsulate all the parameters which are used to make a plan into one place in the code instead of reusing them in 20+ source modules.

[Ethan-DeBandi99]

This work did not yield the benefits initially expected. Additionally, there were some blocking complications. This is no longer being pursued.