Get the file byteLength even if the server does not allow HEAD requests

[severo]

We should use a GET range request with "bytes=0-0"

Alternatively, get it from the first chunk fetch. But note that csv-range does not pass the file byte length to the yielded rows, so we would have to add this metadata.

[severo]

Example can be found in https://github.com/hyparam/hyparquet/blob/master/src/utils.js#L114