Too many tile issue

[micahwoodard]

Is your feature request related to a problem? Please describe.
I'm concerned that in bound mode, things are going to get buggy because it's updating everytime a number changes. If a user accidentally enters a crazy number, then the ui will try and create corresponding z boxes which cause lag and crashing behavior. This will happen in any mode if users add too many tiles but seems the mose likly in bound mode.

Describe the solution you'd like
I think best fix would be to cap the number of z_widgets ScanPlanWidget creates. It's unrealistic for a user to want to individually tweak say over 100 tiles so maybe create a way to cap?

Acceptance Criteria

• prevent crashing if user has too many tiles