If checkpoint is unavailable on on-site generation when remixing, check if there's a new version before defaulting to default model.

Pretty straightforward: Currently if I try to remix an image using WAI-ANI-NSFW-PONYXL V9 (or lower) I get defaulted to base Pony because V9 was disabled for on-site generation when V10 was added. It would be preferable if if went to the newer version automatically and displayed a little notification like “[resource] not available. Replaced with newer available version”.