Engineering guidebook megaupdate v2 (#33062)

Significantly updates the Engineering guidebook (more explicitly the Atmos section) to have a lot more relevant and useful information.

Right now engineering has been getting update after update with no real change to the relevant guidebook entry. This has lead to a lot of out of date information and bad practices being prevalent in the guidebook, something that pains me to read.

Content.Server/Atmos/Portable/PortableScrubberComponent.cs

@@ -1,4 +1,5 @@
 using Content.Shared.Atmos;
+using Content.Shared.Guidebook;
 
 namespace Content.Server.Atmos.Portable
 {
@@ -45,5 +46,12 @@ namespace Content.Server.Atmos.Portable
         /// </summary>
         [DataField, ViewVariables(VVAccess.ReadWrite)]
         public float TransferRate = 800;
+
+        #region GuidebookData
+
+        [GuidebookData]
+        public float Volume => Air.Volume;
+
+        #endregion
     }
 }