Chem guidebook (#17123)

* im good at atomizing. welcome to half-finished chem guides.

* wagh

* e

* save work

* aa

* woweee UI

* finishing the last of it

* don't actually update the engine :(

---------

Co-authored-by: moonheart08 <moonheart08@users.noreply.github.com>

Content.Shared/Chemistry/Reagent/ReagentEffectCondition.cs

@@ -1,5 +1,6 @@
 using System.Text.Json.Serialization;
 using JetBrains.Annotations;
+using Robust.Shared.Prototypes;
 
 namespace Content.Shared.Chemistry.Reagent
 {
@@ -10,5 +11,12 @@ namespace Content.Shared.Chemistry.Reagent
         [JsonPropertyName("id")] private protected string _id => this.GetType().Name;
 
         public abstract bool Condition(ReagentEffectArgs args);
+
+        /// <summary>
+        /// Effect explanations are of the form "[chance to] [action] when [condition] and [condition]"
+        /// </summary>
+        /// <param name="prototype"></param>
+        /// <returns></returns>
+        public abstract string GuidebookExplanation(IPrototypeManager prototype);
     }
 }