Incorrect Terminal Prompt Position When mirror_to_vga is Enabled

[apham727]

When mirror_log_to_vga is enabled, the log messages (usually the Warn log message that the task exited with some value) will overshadow the most recent terminal prompt after a command is run, and the user has to type a character for a new prompt to show up

[kevinaboos]

This isn't a bug, I think that's intended shell behavior.

If a message gets printed after the prompt has been displayed, then the prompt shouldn't be redisplayed until the user presses any key. If that is the current behavior, then it's fine.