While researching https://github.com/dfm/jax-finufft/pull/4#issuecomment-974480880 I came across: https://github.com/flatironinstitute/cufinufft/blob/a8c979e6e70a5303a4384b01a71c86c973a79696/src/memtransfer_wrapper.cu#L88, and was wondering what cufiNUFFT is using streams for. I searched from `streams` and couldn't find any places where this is used, so is this WIP?