make `remote` dependencies more precise

[d-v-b]

We have an optional dependency called remote that includes fsspec and obstore. But fsspec doesn't support http or s3 by default, so users who install zarr[remote] and try to open http or s3 data will still need to install more dependencies.

Over in napari/napari#8268 @Czaki suggested that we could also make this more precise, and declare remote-s3, remote-http, etc, which would effectively be fsspec + s3, fsspec + http, etc. Not sure how this composes with obstore, which has a different pattern of support for remote stores.

Somehow I feel like this was discussed before, but if it was, I couldn't find the issue.

[dstansby]

👍 to this - I just hit the case where I tried installing zarr[remote], but then that didn't install the dependencies needed to open a HTTP store.