Immersive Caves

Adds new cave type: Liminal Cave

Details: Hard to escape and may contain spooky surprises if you dare to enter it

Adds new music for all biomes (each acquirable as a music disk after completing its biome's advancement tree) which did not already have released biome music (All by @SOSSALMON who is credited as an artist):

Aria Negative (this one is fire) - Endstone Cave

Crawling Feeling - Infested Cave

Fungus Amongus - Fungal Caverns

Hard As Obsidian - Obsidian Reserve

Illagers and Illagers - Illager Mine

Just a Blocky Memory - Liminal Cave

Lighting the Gunpowder - Explosive Cave

RUN FOR YOUR LIFE (not acquirable as a music disk) - [REDACTED]

Sanctuary - Panda Reserve

Too Much Coal - Coal Reserve

Uranium Rods - Radioactive Cave