The translate tool should be disabled if the UserCommands plugin is not available

[azeey]

Environment

• OS Version: Ubuntu 22.04
• Source or binary build? Binary 8.5.0

Description

• Expected behavior: If the transform tool is active, it should actually work in translating objects.
• Actual behavior: If the UserCommands plugin is missing on the server side, the transform tool will not work. However, it will activate and give the appearance that it's working. Ideally it should check if the necessary service (provided by UserCommands) is available before activating. Bonus would be to automatically add the UserCommands plugin if it's not running on the server.

Related to: #849
Bad user experiencee: gazebosim/gz-sensors#26 (comment)

Steps to reproduce

1. Run https://github.com/gazebosim/gz-sim/blob/90a7ba7e79e76d50b2cb97e4a20aad5ebba9b023/examples/worlds/gpu_lidar_sensor.sdf
2. Activate the transform tool and move the red box.
3. Click off. The box will snap back to its original position since UserCommands is not running.