VGRoid support (#27659)

* Dungeon spawn support for grid spawns

* Recursive dungeons working

* Mask approach working

* zack

* More work

* Fix recursive dungeons

* Heap of work

* weh

* the cud

* rar

* Job

* weh

* weh

* weh

* Master merges

* orch

* weh

* vgroid most of the work

* Tweaks

* Tweaks

* weh

* do do do do do do

* Basic layout

* Ore spawning working

* Big breaking changes

* Mob gen working

* weh

* Finalising

* emo

* More finalising

* reverty

* Reduce distance

Content.Shared/Procedural/PostGeneration/CorridorDecalSkirtingDunGen.cs

@@ -0,0 +1,29 @@
+using Content.Shared.Decals;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype.Dictionary;
+
+namespace Content.Shared.Procedural.PostGeneration;
+
+/// <summary>
+/// Applies decal skirting to corridors.
+/// </summary>
+public sealed partial class CorridorDecalSkirtingDunGen : IDunGenLayer
+{
+    /// <summary>
+    /// Decal where 1 edge is found.
+    /// </summary>
+    [DataField]
+    public Dictionary<DirectionFlag, string> CardinalDecals = new();
+
+    /// <summary>
+    /// Decal where 1 corner edge is found.
+    /// </summary>
+    [DataField]
+    public Dictionary<Direction, string> PocketDecals = new();
+
+    /// <summary>
+    /// Decal where 2 or 3 edges are found.
+    /// </summary>
+    [DataField]
+    public Dictionary<DirectionFlag, string> CornerDecals = new();
+}