Allow any filepath that *contains* zarr

[will-moore]

Currently, file paths recognised by napari-ome-zarr must end in .zarr or .zarr/.
However, this doesn't support viewing of HCS Wells or Images.

As suggested by DragaDoncila at #55 (comment), this PR allows the path to contain .zarr at any point

To test, open a Well and Image from a Plate. NB: opening the plate itself .zarr/ still works:

# Well (screenshot)
$ napari --plugin napari-ome-zarr https://uk1s3.embassy.ebi.ac.uk/idr/zarr/v0.1/plates/7825.zarr/A/1/

# Image:
$ napari --plugin napari-ome-zarr https://uk1s3.embassy.ebi.ac.uk/idr/zarr/v0.1/plates/7825.zarr/A/1/0/

# Plate:
$ napari --plugin napari-ome-zarr https://uk1s3.embassy.ebi.ac.uk/idr/zarr/v0.1/plates/7825.zarr/

Without this PR, opening an unrecognised path as above gave:

  File "/Users/wmoore/opt/anaconda3/envs/napari-env/lib/python3.9/site-packages/napari/plugins/io.py", line 86, in read_data_with_plugins
    raise ValueError(
ValueError: There is no registered plugin named 'napari-ome-zarr'.
Names of plugins offering readers are: {'ome-types', 'builtins'}

cc @sbesson

[joshmoore]

Interesting!

As a side note, there was some discussion yesterday during the Zarr community call about making /.zarr\// the definitive definition of where the root of a fileset is in V3, but there were other proposals as well.

[sbesson]

This is consistent with the former investigation in #42 (comment).

In terms of implementation, I assume both patterns could also be combined a single *.zarr* or kept separate or clarity.

I think this applies more widely than the HCS use cases as nested image labels or images in the new bioformats2rawlayout will benefit from it. More generically this should allow to point the napari command to any leaf under a top-level .zarr root node as long implements an OME-NGFF specification supported by this plugin.

[will-moore]

I have a marginal preference for keeping *.zarr for clarity - and I like a 1-character PR!
But no strong preference.

[joshmoore]

Thanks, guys. I assume we may be editing these few lines a bit more in the coming weeks, so 👍 for giving @will-moore his one char change ;)