fix: use world-space rotation via global pose override

The bone rest poses have complex non-identity rotations (e.g. LeftUpperArm
euler=(-0.161,-2.760,-2.760)). Applying local rotations on top of these
produces incorrect results. Fix by using set_bone_global_pose_override()
with world-space rotation pre-multiplied on the rest pose basis.

characters/skinned_player_model.gd

@@ -545,7 +545,7 @@ func _process(delta: float) -> void:
 
 func _apply_procedural_animation(data: Dictionary, time: float) -> void:
 	## Applies procedural animation data to the skeleton at the given time.
-	## Uses linear interpolation between keyframe values.
+	## Uses global pose override to set bone transforms relative to their rest pose.
 	if not skeleton:
 		return
 	var tracks = data["tracks"]
@@ -577,9 +577,13 @@ func _apply_procedural_animation(data: Dictionary, time: float) -> void:
 
 		if prev_kf.has("rot") and next_kf.has("rot"):
 			var rot: Vector3 = lerp(prev_kf["rot"], next_kf["rot"], t)
-			# Convert euler angles to Quaternion for set_bone_pose_rotation
-			var quat = Quaternion.from_euler(rot)
-			skeleton.set_bone_pose_rotation(bone_idx, quat)
+			# Get the bone's rest global pose
+			var rest_global = skeleton.get_bone_global_pose(bone_idx)
+			# Apply rotation offset around world axes (pre-multiply)
+			# For locomotion: X = forward/back swing, Y = twist, Z = lateral
+			var world_basis = Basis(Quaternion.from_euler(rot))
+			var new_global = Transform3D(world_basis * rest_global.basis, rest_global.origin)
+			skeleton.set_bone_global_pose_override(bone_idx, new_global, 1.0, true)
 		elif prev_kf.has("pos") and next_kf.has("pos"):
 			var pos: Vector3 = lerp(prev_kf["pos"], next_kf["pos"], t)
 			skeleton.set_bone_pose_position(bone_idx, pos)