build_unlabeled_corpus.py pulls the 34,030 raw-source dialogues that
never got speech_act/slot labels (found via the earlier QA
cross-check) into their own unlabeled.jsonl, forward-filling the
per-dialogue metadata that AI-Hub's CSV export only writes on each
dialogue's first row. Verified against the actual data: 176,605
raw - 142,575 labeled = 34,030, matches exactly.
Claude