Implement blocking homing endpoint and refactor homing logic in mujoco_server.py

Refactor mujoco_server.py and protocol_types.py for external client support

Refactor teleoperation commands to actions in mujoco_server.py and update protocol documentation

Enhance mujoco_server.py and README.md for improved teleoperation and environment management

Enhance mujoco_server.py and UR5 environment for improved teleoperation and episode control

Enhance mujoco_server.py and documentation with camera and scene updates