[Enhancement] Integration with Photopea (free online photo editor)

[ildyria]

Adding the ability to edit images in photopea (an online photo editor similar to photoshop/gimp) would possibly solve all the (future) requests to add editing capabilities to Lychee.

Furthermore the integration does not seem that complex: https://www.photopea.com/api/

[qwerty287]

I also found https://github.com/igorski/bitmappery as an open-source alternative, however, it looks like it doesn't have a way to pre-load an image (i.e. no real integration would be possible - maybe they implement that at some point).