Given the existence of multiple models, it might be useful to insert the name of the .ckpt file into the output metadata (for example, Model: sd-1.4.ckpt, or Model SHA256: FE4EFFF1E174C627256E44EC2991BA279B3816E364B49F9BE2ABC0B3FF3F8556), for reproducibility purposes.

The hash option would be preferable, since many users have been instructed to just rename their model into an unhelpful model.ckpt.
The hash could be cached into a .txt/.json file based on the (date last modified, file size) key, so that it doesn't have to be recomputed every time webui.py is launched.