rust/sedona-spatial-join: Improve memory estimation and serialization for EvaluatedGeometryArray

[paleolimbot]

There is at least one place where we may be double counting a large chunk of memory in the EvaluatedBatch:

        // NOTE: sometimes `geom_array` will reuse the memory of `batch`, especially when
        // the expression for evaluating the geometry is a simple column reference. In this case,
        // the in_mem_size will be overestimated. It is a conservative estimation so there's no risk
        // of running out of memory because of underestimation.
        let record_batch_size = get_record_batch_memory_size(&self.batch)?;
        let geom_array_size = self.geom_array.in_mem_size()?;
        Ok(record_batch_size + geom_array_size)

This might explain an issue we ran across when trying to enable this by default where we determined we'd need to set the memory pool size to more than twice as much memory as was required for a join used in the released post (my reading of that comment is that we would be reserving ~2x as much memory as was required for most joins but I have not investigated).

[paleolimbot]

Something else that came up in #737 is that we are potentially double serializing the geometry (in addition to the geometry f32 rect bounds, which may or may not be needed depending on the index implementation, or may or may not be faster to compute than to compress depending on the compression options / speed of bounding).