Add roofs on roof buildings, add glass roof on entrance

[PatrikLundell]

Summary

None

Purpose of change

• Add explicit roofs on rooftop buildings rather than relying on add_roofs magic.
• Add glass roof on secret lab office building entrance.

Describe the solution

• Add a layer for the roofs and hook it into the infrastructure.
• Use the entrance roof from the building the lab is based on rather than open air.

Describe alternatives you've considered

Testing

Debug spawn facilities, teleport to them, examine them.

Additional context