That makes a lot of sense! Kind of makes you wish for UIDs or something like what Godot/Unity use to track that exact thing, but I can't see that being a very practical solution for a tool like impart. I quite like that it doesn't generate or mess with files. I suppose having impart detect new files and letting you easily label them is easy enough to do, I doubt people change file structure super often.
ORA is OpenRaster Image Files, generally used by open source art programs (Krita, Drawpile, Gimp, MyPaint, Blender (for 2D images), etc, though photoshop and clip studio can also output them). Since it's an open format it shouldn't be too hard to look at it's guts since it's all documented on the web, I know that Deevad on Github has already made a ORA thumbnailer tool which if you're lucky might be compatible with Impart for you to just use and make the tool tremendously more versatile without needing to reinvent wheels.
Also huge fan of your art by the way. When I saw the thumbnail for this tool on itch I had to do a double-take, I'd recognize that rendering style anywhere on the internet/did not know you were a programmer as well. Very cool stuff!