Derived index for the biglam/british-library-book-images siglip2_embeddings config, built for a text-to-image search Space.
embeddings.npy - float32 (1080814, 1152), L2-normalized, rows ordered by split: covers, embellishments, medium, plates
metadata.parquet - fname, date, year, image_type, split (no vectors)
split_ranges.json - row range per split, so a split filter is a slice
