Fallback to unchanged image if processor fails to return a valid image (e.g. SVG)

Hello!

We have in our website a field that supports the following image formats: PNG, JPEG, SVG.

This field is set to use an image style that has a pipeline running reSmush.it. The big issue here is that, since the module doesn't support SVG optimization yet, we don't have a pipeline for it, and if the user uploads an SVG image, the image is not generated in its respective /style folder.

My suggestion is to fallback to copying the original image to this folder in case the processor doesn't support its format or anything goes wrong in the process.

Thank you!