Revert biome rework (#38724)

* Revert "Fix world generation (#38713)"

This reverts commit 10fa6ff4af.

* Revert "Biome rework (#37735)"

This reverts commit fe7b96147c.

Content.Shared/Procedural/PostGeneration/CorridorClutterDunGen.cs

@@ -0,0 +1,20 @@
+using Content.Shared.EntityTable;
+using Content.Shared.Storage;
+using Robust.Shared.Prototypes;
+
+namespace Content.Shared.Procedural.PostGeneration;
+
+/// <summary>
+/// Adds entities randomly to the corridors.
+/// </summary>
+public sealed partial class CorridorClutterDunGen : IDunGenLayer
+{
+    [DataField]
+    public float Chance = 0.05f;
+
+    /// <summary>
+    /// The default starting bulbs
+    /// </summary>
+    [DataField(required: true)]
+    public ProtoId<EntityTablePrototype> Contents;
+}