Adds saltpetre crystals, which grind into saltpetre (#25050)

* Added saltpeter crystal, a way to make them, and sprites.

* comment changes

* forgot to undef

* actually undefing this time

* raises saltpeter crystal yield when ground to 8

I did some play testing and it simply takes too many clicks to pump in the ammonia required to get the amount of saltpeter you need.

* The compost bin being full of compost no longer hinders your saltpetre production

* rebuild TGUI

* Allows the compost bin to accept ammonia directly from plants that contain it

* adding the K back to KNO3

* Minor ui adjustments

* Compost bin can use ash now

* I am made of stupid.

* fixing a tiny little offset in the biomass bar

* Icon update, new description for Saltpetre crystals, style fixes and recompile tgui

* period

* minor changes

* rebuild TGUI

* Apply suggestions from code review

Signed-off-by: Matt <116982774+Burzah@users.noreply.github.com>

---------

Signed-off-by: Matt <116982774+Burzah@users.noreply.github.com>
Co-authored-by: Burzah <116982774+Burzah@users.noreply.github.com>

code/game/objects/items/stacks/sheets/sheet_types.dm

@@ -11,6 +11,7 @@
  * Brass (clockwork cult)
  * Bones
  * Plastic
+ * Saltpetre Crystal
  */
 
 /*
@@ -692,3 +693,16 @@ GLOBAL_LIST_INIT(plastic_recipes, list(
 
 /obj/item/stack/sheet/plastic/five
 	amount = 5
+
+/*
+ * Saltpetre crystal
+ */
+
+/obj/item/stack/sheet/saltpetre_crystal
+	name = "saltpetre crystal"
+	desc = "A bunch of saltpetre crystals. Can be ground to get liquid saltpetre that can be used to dope hydroponics trays and soil plots."
+	singular_name = "saltpetre crystal"
+	icon = 'icons/obj/stacks/organic.dmi'
+	icon_state = "sheet-saltpetre"
+	item_state = "sheet-saltpetre"
+	origin_tech = "materials=1;biotech=1"