Rapid Router Level editor houses

[lauracumming]

Add option to add houses to maps for multiple deliveries.

https://www.codeforlife.education/rapidrouter/level_editor/#

Here is the new graphic for the button: https://drive.google.com/file/d/1Wz1Rezca4F9vi8NpZHhW28uRvsza4l9S/view?usp=drive_link

And here is some context:

https://api.zenhub.com/attachedFiles/eyJfcmFpbHMiOnsibWVzc2FnZSI6IkJBaHBBN1AzQXc9PSIsImV4cCI6bnVsbCwicHVyIjoiYmxvYl9pZCJ9fQ==--727d645f5c24d30cab09114bc7527b0783103a04/Screenshot%202024-03-20%20at%2015.49.53.png" alt="Screenshot 2024-03-20 at 15.49.53.png" />