Add Fine-tuned checkpoint type

"Fine-tuned" is a category for all checkpoints that were created by fine-tuning non base SD models. (e.g. Anything 3.0 - Fine-tuned NovelAI)

Concept:

Example:

I think Trained already covers this. I don't that any of the checkpoints on Civitai have been trained from scratched. Marking a checkpoint as trained just means you added your own training data to the fine-tune, as opposed to just recombining existing checkpoints.