feat: add `by_prefix` similar to `by_suffix`

[olexsmir]

Example:

[Yolo390]

Hi guys, any news on this one ?!

[alex-courtis]

Pull requests are gratefully appreciated.

[BBboy01]

This issue has been resolved by #322, but not suitable for Dockerfile.xxx some kind of "prefixed" file type, is this ok to add a icons_by_file_prefix table?

[alex-courtis]

I hadn't noticed this one, thanks for bringing it up.

Yes, we could add an icons_by_file_prefix, with name and extension taking precedence so as not to break existing behaviour.