### Description

It would be really great if [CircleProcessor.java](https://github.com/elastic/elasticsearch/blob/0699c9351f1439e246d408fd6538deafde4087b6/x-pack/plugin/spatial/src/main/java/org/elasticsearch/xpack/spatial/ingest/CircleProcessor.java) could be published in some maven artifact.
We are thinking to convert Geoshape Circle into Geoshape Polygon on application side instead of ElasticSearch Server side. The benefits of it is that it would make possible for us to choose `error_distance` dynamically depending on different conditions.
With direct code access to [CircleProcessor.java](https://github.com/elastic/elasticsearch/blob/0699c9351f1439e246d408fd6538deafde4087b6/x-pack/plugin/spatial/src/main/java/org/elasticsearch/xpack/spatial/ingest/CircleProcessor.java) and [SpatialUtils.java](https://github.com/elastic/elasticsearch/blob/0699c9351f1439e246d408fd6538deafde4087b6/x-pack/plugin/spatial/src/main/java/org/elasticsearch/xpack/spatial/SpatialUtils.java) it would be possible to make application side custom conversion logic.
ElasticSearch version: >= 8
x-pack/plugin/spatial/src/test/java/org/elasticsearch/xpack/spatial/ingest/CircleProcessorTests.java
int numSides = randomIntBetween(4, 1000);
        Geometry geometry = SpatialUtils.createRegularShapePolygon(circle, numSides);
        MappedFieldType shapeType = new ShapeFieldType(fieldName, true, true, Orientation.RIGHT, null, Collections.emptyMap());
        ShapeQueryProcessor processor = new ShapeQueryProcessor();
        SearchExecutionContext mockedContext = mock(SearchExecutionContext.class);
        when(mockedContext.getFieldType(any())).thenReturn(shapeType);
        Query sameShapeQuery = processor.shapeQuery(geometry, fieldName, ShapeRelation.INTERSECTS, mockedContext, true);
        Query centerPointQuery = processor.shapeQuery(
            new Point(circle.getLon(), circle.getLat()),
            fieldName,
            ShapeRelation.INTERSECTS,
            mockedContext,
            true
        );
        try (Directory dir = newDirectory(); RandomIndexWriter w = new RandomIndexWriter(random(), dir)) {
            Document doc = new Document();
            CartesianShapeIndexer indexer = new CartesianShapeIndexer(fieldName);
            for (IndexableField field : indexer.indexShape(geometry)) {
                doc.add(field);
            }
            w.addDocument(doc);
            try (IndexReader reader = w.getReader()) {
                IndexSearcher searcher = new IndexSearcher(reader);
                assertThat(searcher.search(sameShapeQuery, 1).totalHits.value, equalTo(1L));
                assertThat(searcher.search(centerPointQuery, 1).totalHits.value, equalTo(1L));
            }
        }
    }
}