Update SECD metadata to Zenodo maintenance release

Finalize SECD dataset card

Add SECD Hugging Face overview graphic

Complete and validate SECD dataset card

Restore HF metadata and finalize SECD dataset card

Finalize SECD dataset card

Push 7th_chords_loose with native Audio features

Push harmonic_intervals_loose with native Audio features

Push triads_loose with native Audio features

Push 7th_chords_strict with native Audio features

Push harmonic_intervals_strict with native Audio features

Repair triads_strict Audio card metadata without replacing audio data

Pass Audio features to triads_strict builder

Fix triads_strict Audio schema

Declare Audio feature in dataset metadata

Configure triads_strict dataset

Fix Audio feature metadata for Dataset Viewer

Add private triads_strict prototype

initial commit