DungeonData rework (#37172)

* DungeonData rework

Back to fields, serializes better, just make new layers dumby.

* wawawewa

* Fix this

* Fixes

* review

* thanks fork

* fix

Content.Shared/Procedural/PostGeneration/RoomEntranceDunGen.cs

@@ -1,11 +1,18 @@
+using Content.Shared.EntityTable;
+using Content.Shared.Maps;
+using Content.Shared.Storage;
+using Robust.Shared.Prototypes;
+
 namespace Content.Shared.Procedural.PostGeneration;
 
 /// <summary>
 /// Places tiles / entities onto room entrances.
 /// </summary>
-/// <remarks>
-/// DungeonData keys are:
-/// - Entrance
-/// - FallbackTile
-/// </remarks>
-public sealed partial class RoomEntranceDunGen : IDunGenLayer;
+public sealed partial class RoomEntranceDunGen : IDunGenLayer
+{
+    [DataField(required: true)]
+    public ProtoId<ContentTileDefinition> Tile;
+
+    [DataField]
+    public ProtoId<EntityTablePrototype> Contents;
+}