Support Lucene push-down for distance filtering with ST_DISTANCE

[craigtaverner]

Based on the specification at #108212, we have implemented the ST_DISTANCE function in the PR at #108764.

However, this does not perform any Lucene pushdown, and so will run slow for larger datasets. One approach to getting lucene pushdown to work is to rewrite the predicate from:

FROM airports
| WHERE ST_DISTANCE(location, TO_GEOPOINT("POINT(12 55)")) < 500000

to:

FROM airports
| WHERE ST_INTERSECTS(location, TO_GEOSHAPE("CIRCLE(POINT(12 55), 500000)"))

This re-write would NOT occur at the query parsing stage (as implied above), but should be done during Logical Plan optimization. Then the existing lucene pushdown for ST_INTERSECTS should work.

[elasticsearchmachine]

Pinging @elastic/es-analytical-engine (Team:Analytics)