Add Omron composite controllers and menagerie Robotiq 2F-85 model

[JiyunJang-24]

Supports IIWA/Jaco/UR5e-Omron mobile-base composites used by the robocasa cross-embodiment dataset pipeline (see JiyunJang-24/robocasa), and swaps in the mujoco_menagerie Robotiq 2F-85 model (the one the BARX/atomic_new recordings actually used) as an alternative to robosuite's stock 2f85_robosuite.xml gripper.

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