feat(pipelines): compute_harmonization_diagnostics — long-format pre/post ComBat for viz

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

refactor(mri): use core.determinism + core.storage helpers

fix(mri): handle all-constant features; tighten variance threshold; reorder log

feat(mri): add run_pipeline orchestrator + CLI (NIfTI dir → ComBat Parquet)

fix(mri): pin ComBat transitive deps; clarify np.round(14) intent; guard inputs

feat(mri): add harmonize_combat wrapper around neuroHarmonize.harmonizationLearn

refactor(mri): bind ROI_STATS to callables; guard volume/mask shape mismatch

feat(mri): add extract_features_from_volume (8 ROI octants × 6 stats)

fix(mri): warn on all-False mask; document 6-connectivity erosion caveat

feat(mri): add mask_brain (intensity threshold + morphological opening)

feat(mri): add is_valid_volume guard for NaN/inf/shape/dtype on 3-D arrays