feat(bbb): log run params, metrics, and parquet artifact to MLflow

feat(bbb): switch processed output to Parquet for dtype preservation

refactor(bbb): pin LF lineterminator; move DEFAULTs to top; reject dir output

feat(bbb): add run_pipeline orchestrator + CLI entrypoint with idempotent writes

fix(bbb): guard empty input; truncate index log; add KeyError + log tests

feat(bbb): expand SMILES → Morgan FP into model-ready DataFrame with drift logging

refactor(bbb): migrate to MorganGenerator API; consolidate test imports

feat(bbb): add Morgan fingerprint extraction with shape/dtype guarantees

refactor(bbb): tighten is_valid_smiles signature; document RDLogger global effect

feat(bbb): add SMILES validity guard with RDKit + test fixture