What is Microsoft best practice for handling *planned* breaks in bookings for a resource assigned to long Agreements Booking setups, like a maintenance agreements that has booking that takes 8 hours. 

In reality that booking would have to be scheduled for 9 hours, giving employee room for breaks (incl lunch) - by working laws if nothing else.

How should that be set up and scheduled properly in FS? 

Working hours does have break capability but it is not effecting a booking (bookable resource booking) at all. And the schedule board when summarizing hours in the daily view still show 9 hours although booking is scheduled with booking start time long before break time, and duration way past break time.

I know there is support for resource to set ongoing booking in Break status, but that is more for actuals not planning.