Detect if mouse has not moved

[dessant]

There are currently two cases where buster-client silently fails to move the mouse:

• When Wayland is used on Linux
• The browser or buster-client have not been whitelisted in the accessibility settings on macOS

It should be seen if robotgo returns any error in these cases, and if not, we can simply check if the mouse has moved after the first command, then show a platform-specific error message.