Broken support for `write_empty_chunks` with Zarr v3

What happened?

The to_zarr() method accepts a keyword argument write_empty_chunks but the Zarr 3 backend no longer supports it. Instead, it can accept config={'write_empty_chunks': False} but to_zarr does not.

xarray 2025.1.2, zarr 3.0.3

What did you expect to happen?

It would write the data in Zarr skipping the empty chunks..

Minimal Complete Verifiable Example

ds = xr.Dataset(...)
ds.to_zarr(write_empty_chunks=False, ...)  # Raises: TypeError: Group.create_array() got an unexpected keyword argument 'write_empty_chunks'

ds.to_zarr(config={'write_empty_chunks': False}, ...)  # Unexpected kwarg 'config'

MVCE confirmation

• Minimal example — the example is as focused as reasonably possible to demonstrate the underlying issue in xarray.
• Complete example — the example is self-contained, including all data and the text of any traceback.
• Verifiable example — the example copy & pastes into an IPython prompt or Binder notebook, returning the result.
• New issue — a search of GitHub Issues suggests this is not a duplicate.
• Recent environment — the issue occurs with the latest version of xarray and its dependencies.

Relevant log output

Anything else we need to know?

May I also suggest that you add a zarr_backend_kwargs argument that gets passed to the Zarr backend?

Environment

Start at the to_zarr() entry point and trace how its keyword arguments reach the Zarr 3 backend, reproducing the provided write_empty_chunks example with xarray 2025.1.2 and zarr 3.0.3. Done means writing succeeds while skipping empty chunks, with the unsupported argument no longer reaching Group.create_array().