OT Star Shaped Fire Mortar Shells Ignoring Cave Roof

## Testmerges
#10999: 'Fix of various plane related issues' by Blundir at commit f85a7153c4
#11136: 'Coms Rolling Encryption & Punchcards' by Drulikar at commit 2d55de8084
#10954: 'Liquid fuel decals now ignite & Toxic no longer destroys weeds' by Drulikar at commit fd225b3883
#10611: 'White Antre Research Facility - Ground Map' by Steelpoint at commit ae4031871b
#9948: '[code bounty] Despoiler' by cuberound at commit 4827cb4c28
#11170: '[WIP] Yautja Survivor' by realforest2001 at commit 8ddd5d30e8
#10908: 'Adds additional checks to pouncing up a z level' by Git-Nivrak at commit 131d5e093b
#11249: '[s][dnm] Return Ice Colony Classic to CM for the Holiday Season (round 2)' by Detective-Google at commit 92a8f559ae
#11284: 'Fixes an attachment exploit' by Git-Nivrak at commit 862d46f8d7

## Round ID
31271

## Description of the bug
OT star flames are going through cave walls and into caves.

## What's the difference with what should have happened?
OT shells already ridiculous. At least leave the caves alone please.

## How do we reproduce this bug?
1) Fire OT max cap star shell near caves
2) Observe the flames.

## Attached logs
```
N/A
```

## Additional details
- Author: Superwelder
- Admin: SmellyHippie
- Note: For clarity, the origin of the shell was outside of the caves, however the fire traveled through solid walls. This seems like a common theme with custom OT shells.