Fills Ozan order-board row #4 (avatar_pray): kneel toward statue, hands together,
hold. Mixamo Kneel held at deepest-kneel frame (184) for the legs + Praying looped
forward on the upper (rotation-only graft), retargeted to the shared Quaternius rig.
Loop QC SMOOTH (0.00deg seam). Adds tools/merge_layer.py + tools/merge_hold.py
(upper/lower track compositing: layer and hold modes).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
