Modify scroll bar behavior during task execution to allow devs to read progress

[cfdude]

If you ask Roo to execute a task and it starts its output, the scrollbar always pushes the window down to the latest action that is happening. If you attempt to scroll up while a task is running, you will get interrupted by Roo and the scrollbar will push back down to the bottom where the latest thing is happening.

The desired preference here would be if a user moves the scrollbar X% away from the bottom that Roo would not force the scrollbar to move to the latest content. This would allow users to review changes while actively running. If the user puts the scrollbar back below the X% then active scrolling would be enabled showing the latest updates for each activity or line being returned without having the user force a manual scroll to the bottom on their own.