Explore creating clips from images

[soundchaser128]

Thoughts:

• Need to be able to opt-in during folder scanning (default should be off, I think, at least for now)
• Allow adding images from Stash as well
• Need filters for the grid views.
• How to represent images in the marker view? (possibly just have them as different-looking cards that let you specify the length)

For ffmpeg: https://www.bannerbear.com/blog/how-to-do-a-ken-burns-style-effect-with-ffmpeg/