Snowdin and caves fluff and zoning removal (#95770)

## About The Pull Request

<img width="245" height="468" alt="image"
src="https://github.com/user-attachments/assets/e7924766-cf9a-4ca0-b3fb-a668d3d2cec0"
/>

## Why It's Good For The Game

shouldve been removed with the first pr

## Changelog

Removes everything for the caves and snowdin away missions except for
the original caves area because i used that in heretic, whoops.

not player facing there should be no CL

code/datums/shuttles/snowdin.dm

@@ -1,11 +0,0 @@
-/datum/map_template/shuttle/snowdin
-	port_id = "snowdin"
-	who_can_purchase = null
-
-/datum/map_template/shuttle/snowdin/mining
-	suffix = "mining"
-	name = "Snowdin Mining Elevator"
-
-/datum/map_template/shuttle/snowdin/excavation
-	suffix = "excavation"
-	name = "Snowdin Excavation Elevator"