chore: rename HF owner HlexNC → arudaev across all references

docs: document CLAHE, label smoothing, TTA, and ensemble in hub.py, CLAUDE.md, README

fix: update model card templates and diagram PNGs for 320px dataset

Switch training dataset to HlexNC/chest-xray-14-320 (320px)

Add diagram PNG generation script and fix pipeline Mermaid source

Fix model card dataset revision display to include full hash

Fix app checkpoint-aware model instantiation; dual Kaggle token paths

v2: SE attention, AMP, grad accumulation, rich model cards with Mermaid

Fix configure_hf_runtime mkdir in non-Kaggle environments

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