fix: increment cache buster to force HuggingFace rebuild

fix: add cache-busting ARG to force HuggingFace rebuild

fix: comprehensive error handling, UI fixes, and transaction protection

fix: add database migrations at container startup and deployment tests

feat: add React frontend with nginx reverse proxy

fix: use BuildKit cache mounts for proper non-root permissions

fix: set cache directory for non-root container execution

feat: complete Wall Construction API with nested progress endpoint and HuggingFace deployment