fix(resize_320): build and dispatch the raw-source Kaggle pipeline

Add HF hub utilities, fix Kaggle secret injection via dataset source

Align Kaggle kernel slugs with live notebook refs

Handle KGAT Kaggle tokens in dispatch CLI

Restore src/data package, fix HF Space bootstrap, improve Kaggle/CI wiring

Fix CI, unblock Kaggle training dispatch, upgrade demo app for HF Spaces

Replace notebooks with scripts + Kaggle dispatch, add HF data pipeline Space