Riff Level 2 public-beta model package

DEPLOYMENT: public beta. Model quality and future compatibility are not guaranteed.

The frozen EfficientAT mn10_as_mels_64 checkpoint and implementation originate
from fschmid56/EfficientAT at the revision recorded in manifest.json. EfficientAT
source is MIT licensed. This beta includes the derived model weights and records
their exact upstream revision and hashes in manifest.json and SHA256SUMS.json.

Training supervision includes MTG-Jamendo labels and offline Essentia-derived teacher
values. No Essentia code, binary, graph, or model is contained in this package.
The public beta discloses this research-derived supervision provenance. No stable
or commercial-quality claim is made.

LiteRT conversion uses litert-torch. Android execution uses Google LiteRT.