Go2 rerun blueprint has ugly bg / grid is under the costmap

bg should be pure black, grid should be lifted .5m or something

shoud be this:

<img width="1214" height="976" alt="Image" src="https://github.com/user-attachments/assets/ca140476-443e-49c4-9243-c7c81433eaf6" />

not this:

<img width="1142" height="1406" alt="Image" src="https://github.com/user-attachments/assets/fcb7c1ce-67db-48c0-801b-8448d6239b8b" />