filenaming

per https://github.com/axodotdev/axoasset/pull/2#discussion_r1066587304 via @Gankra

currently if fetching a remote asset where the origin path is a url whose final segment is *not* identifiable as a filename, we do the following transform:

> https://mywebsite.com/some/path/image.png
> /some/path/image.png
> _some_path_image.png
> some_path_image.png

for several reasons this is suboptimal and we should review this and how we name files in general.

The issue does not name files, tests, or a code entry point. Start by tracing how remote asset URLs are turned into filenames, using the example in the issue as a reference. The issue asks for a broader review of naming, but does not specify a desired result or criteria for completion.

Written by the indexing model from the issue text.