Wrong joint ids mapping when there are non-actuated ball joints #475

In mjlab\src\mjlab\entity\entity.py line 892, the initialization process treat all joints as hinge type. Though in line 924 it correctly expand the joint adress (3 for ball vel and 4 for ball quat) , the joint_ids is not modified.
Then when write_joint_state is called, the map between joint_ids and self.indexing.joint_q_adr & self.indexing.joint_v_adr are wrong.