feat: add /dataset/snapshot/{save,restore,list} for cross-module switches

feat: add /model/export endpoint for joblib bundle download

feat: add pose, general-objects, skin, brain, tabular endpoints

feat: full jet colormap composite heatmap (matches medical Grad-CAM style)

fix: focused jet heatmap with percentile thresholding

feat: x-ray densenet-all (AUC 0.86), pseudo-CAM, thread pinning, /models/classes endpoint

fix: x-ray endpoint — sigmoid logits, pre-resize large images, safer Grad-CAM hooks

feat: add 4 new models — X-ray/Grad-CAM, YOLO animals, Food ViT, Bird EfficientNetB2

fix: add HF Space config README.md

feat: upgrade to EfficientNetV2-S + add torch/torchvision deps