Adds rare life crystals and structures that appear in caves between y = -64 and y = 32.

The default config allows the player to consume 10 max and gain a heart per crystal but both of those numbers can be changed.

Additional config options are provided to disable generation and also to make the generation more rare or common.

Generation example:

This is a slightly compressed visualiztion of generation with default config. Each floating lava block represents a life crystal at a random height below it.

(There is a slight bias in this example as I had to use an ocean so the blocks could be visible but oceans fit the generation conditions more commonly than other biomes)

Update 1.1:

Added the Mini Heart Lantern which is also fully configurable, more sizes are to come but for now this is just a test.

(it's also a very cute block that I think can work in a lot of builds)

Update 1.2:

Added a few configurable underground structures and rebalanced some generation

NOTES FOR MODPACK MAKERS:

If you want to give life crystals as rewards or add them to lootables, you need to use "simplelifecrystals:life_crystal_item" as "simplelifecrystals:life_crystal" is the block. They are separated for a reason I've forgotten and I don't fancy rewriting to find out why.
Most of the structures are just made of stone/deepslate variants (bricks, walls, slabs, etc) so likely can't break progression. The heart chamber structure, however, generates with red carpet which could break progression in some fine tuned packs.

Bonus fun fact, the command "/item replace entity @a armor.head with simplelifecrystal:life_crystal" makes it look like everyone has cat ears.