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/BiomeDunGen.cs

@@ -0,0 +1,14 @@
+using Content.Shared.Parallax.Biomes;
+using Robust.Shared.Prototypes;
+
+namespace Content.Shared.Procedural.PostGeneration;
+
+/// <summary>
+/// Generates a biome on top of valid tiles, then removes the biome when done.
+/// Only works if no existing biome is present.
+/// </summary>
+public sealed partial class BiomeDunGen : IDunGenLayer
+{
+    [DataField(required: true)]
+    public ProtoId<BiomeTemplatePrototype> BiomeTemplate;
+}