fix(miku): correct scale + animation playback

- Fixed Blender export: remove FBX armature modifier before scaling,
  then transform_apply(scale=True) before creating new armature
- Model now exports at correct 1.8 unit height (verified in Blender)
- SkinnedPlayerModel now polls MovementStateMachine in _process
  to drive animations based on movement state
- Player 1 gets Miku at origin, others get procedural humanoid at y=-0.9

debug/test_level_builder.gd

@@ -370,14 +370,15 @@ func _spawn_player(pid: int) -> CharacterBody3D:
 		player.set_script(mover_script)
 
 	# Visual Model for Player
-	# Player 1 gets the Miku skinned model, others get procedural humanoid
 	if pid == 1:
+		# Miku: use the rigged GLB model with its own armature
 		var skinned = load("res://characters/skinned_player_model.gd").new()
 		skinned.name = "SkinnedModel"
 		skinned.model_path = "res://assets/characters/skins/miku_rigged_final.glb"
-		skinned.position = Vector3(0, -0.9, 0)
+		skinned.position = Vector3.ZERO  # Model origin = player origin
 		player.add_child(skinned)
 	else:
+		# Default: procedural humanoid
 		var humanoid = load("res://characters/humanoid_model.gd").new()
 		humanoid.name = "HumanoidModel"
 		humanoid.color = Color(0.2, 0.4, 0.8)