Materials Repath (#22388)

Soft-ish port of https://github.com/NebulaSS13/Nebula/pull/540. Except
we call them singletons.

Repaths all materials as singletons instead of datums, and replaces
material defines from strings to paths so that we can just run
GET_SINGLETON instead of needing to use SSMaterials. This is Step One.

This PR has no player-facing changes.

changes:
  - refactor: "Repaths /material to /singleton/material."
- refactor: "Replaces all material string defines to path defines,
replacing SSmaterials procs w/ GET_SINGLETON instead."
- refactor: "Removes all material var edited objects from all maps,
adding new presets where necessary."
- refactor: "Updates recipes unit test to run all recipes against all
material singletons."

---------

Signed-off-by: Batrachophreno <Batrochophreno@gmail.com>
Co-authored-by: kano-dot <bhutanlikanoxy@gmail.com>

code/modules/mob/living/simple_animal/hostile/phoron_worm.dm

@@ -71,7 +71,7 @@
 
 	if(istype(A, /obj/item/stack/material))
 		var/obj/item/stack/material/P = A
-		if(P.material.name == MATERIAL_PHORON)
+		if(P.material.type == MATERIAL_PHORON)
 			visible_message(SPAN_WARNING("\The [src] starts consuming \the [P]..."), SPAN_NOTICE("You start consuming \the [P]."))
 			if(!do_after(src, 1 SECOND, P))
 				return