Metabolism refactor (#4395)

* metabolism -> respirator, add reageanteffect and reagenteffectcondition, start on metabolizercomp/system

* move LiverBehavior metabolism logic to Metabolizer

* minor tweaks and update all YAML

* how about actually taking conditions into account

* off by one

* removals

* reviews

Content.Shared/Chemistry/Reagent/ReagentEffect.cs

@@ -0,0 +1,23 @@
+using System.Collections.Generic;
+using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Serialization.Manager.Attributes;
+
+namespace Content.Shared.Chemistry.Reagent
+{
+    /// <summary>
+    ///     Reagent effects describe behavior that occurs when a reagent is ingested and metabolized by some
+    ///     organ. They only trigger when their conditions (<see cref="ReagentEffectCondition"/>
+    /// </summary>
+    [ImplicitDataDefinitionForInheritors]
+    public abstract class ReagentEffect
+    {
+        /// <summary>
+        ///     The list of conditions required for the effect to activate. Not required.
+        /// </summary>
+        [DataField("conditions")]
+        public ReagentEffectCondition[]? Conditions;
+
+        public abstract void Metabolize(IEntity solutionEntity, Solution.Solution.ReagentQuantity amount);
+    }
+}