docs: provenance + EU AI Act Art. 53 status

card: v3/v3c versions + modelSpanCost integration (span<1.5 @ agree>82%)

v3 best checkpoint

add v3c (EGSet12 + span-regularizer)

add v3 (+EGSet12, val 0.829)

add v1 (78.59%, low-movement) fallback

card: versions table + cost.move frontier; fix stale metric (live=82.70%); note v3/EGSet12 in training

Update tab labeler best checkpoint

model card

symbolic tab fingering scorer (GuitarSet, CC BY 4.0)

initial commit