deploy-hf: try push first, create-Space on failure (stop spurious exit-22)

checkpoint-7: fix HF Gradio HfFolder import + bump checkout to Node 24

checkpoint-6: pin HF Space python_version=3.11 + audioop-lts safety net

checkpoint-4: fix HF deploy + wire XGBoost bundles on the Space

checkpoint-3: comparison report, FastAPI, Gradio, HF Space deploy