Simplify charcoal recipe a little

[TobleroneSwordfish]

[CHARCOAL] (I typed this instead of [CHEMISTRY] and it made me laugh so now it stays here)

About the PR

Simplifies the recipe for charcoal to just be (1) carbon + (1) ash = (1) charcoal + (1) steam (the ash is damp or something okay) with a secondary recipe of (1) carbon + (1) ash + (2) steam = (4) charcoal
The idea is that if you make it in an open container the steam evaporates and you lose yield compared to making it in a closed container.

Why's this needed?

Starting to address some of the rough edges of the chemistry rework. Someone asked in discord earlier how charcoal is made and I realised the explanation should not take half a page for a very basic medical chem. This version removes the common "all my charcoal vanished :(" complaint and brings the recipe more in line with its in-game level of power/complexity.

Changelog

(u)LeahTheTech
(*)Simplified the charcoal recipe: (1) Carbon + (1) Ash => (1) Charcoal + (1) Steam, with additional charcoal yield if the steam is prevented from evaporating.

[Flaborized]

I think this is a fine change and I probably overtuned charcoal's recipe a bit, though I think the whole 'use condensers to pipe steam into a reaction' idea is Cool and could be re-utilized for some other recipe (if not the Super Basic Healing Chem one)