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 :(

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

Content.Server/Chemistry/ReagentEffects/ModifyLungGas.cs

@@ -1,6 +1,7 @@
 using Content.Server.Body.Components;
 using Content.Shared.Atmos;
 using Content.Shared.Chemistry.Reagent;
+using Robust.Shared.Prototypes;
 
 namespace Content.Server.Chemistry.ReagentEffects;
 
@@ -9,6 +10,10 @@ public sealed class ModifyLungGas : ReagentEffect
     [DataField("ratios", required: true)]
     private Dictionary<Gas, float> _ratios = default!;
 
+    // JUSTIFICATION: This is internal magic that players never directly interact with.
+    protected override string? ReagentEffectGuidebookText(IPrototypeManager prototype, IEntitySystemManager entSys)
+        => null;
+
     public override void Effect(ReagentEffectArgs args)
     {
         if (args.EntityManager.TryGetComponent<LungComponent>(args.OrganEntity, out var lung))