Remove PrefixTreeStrategy.makeDistanceValueSource support [LUCENE-9689]

PrefixTreeStrategy.makeDistanceValueSource reads all the full length terms and puts them into memory.  And it does this rather crudely; it's not efficient, unlike much other Lucene code.  Furthermore, it can be mis-used when non-point data is put into the RPT, leading to undefined results.  We could add "isPointsOnly" to make it safe, but I think support for this ought to be removed; instead users can use LatLonDocValuesField.newDistanceSort for geospatial data (surface of earth), or PointVectorStrategy for general 2D.

---
Migrated from [LUCENE-9689](https://issues.apache.org/jira/browse/LUCENE-9689) by David Smiley (@dsmiley)

Start at PrefixTreeStrategy.makeDistanceValueSource and inspect its callers and related geospatial strategy APIs. Review the issue’s suggested LatLonDocValuesField.newDistanceSort and PointVectorStrategy alternatives. Done means the unsupported method is removed safely, with affected references and relevant tests or documentation updated.

Written by the indexing model from the issue text.