write to zarr v3 (prototype?)

[toloudis]

Feature Description

With zarr-python now supporting zarr V3, we can start to experiment with sharded writes.
OME-Zarr 0.5 spec depends on zarr v3. I'm not sure we want to wholeheartedly put ome-zarr 0.5 into production but we can get a head start.

Use Case

Zarr v3 has sharding which can greatly decrease the number of files. Also the zarr-python library has much improved async write concurrency.

Solution

Test out writing zarrv3 arrays with various sharding and chunking sizes. Could start with a totally separate writer , or try to implement a writer for omezarr0.5.