[Feature] Download image with original filename

[vidyava]

Is your feature request related to a problem? Please describe.
Any time you go to download an image from Stash, it's presented as "image.jpg" (extension dependent on original filename). This becomes a hassle when you want to download more than one picture without overwriting/renaming every time.

Describe the solution you'd like
Either to present the image as the original filename so the user's browser defaults to saving with that name, or just some sort of "Download original" button that preserves the name.

Describe alternatives you've considered
In some instances this can be solved by clicking on the "Path" link if you have local access and the paths are the same, but if you're running Stash on a server (without exactly matching mount points) or docker container with non-matched paths, this would still fail.

Additional context

Thanks!