chore: add room configs back in

At the moment, MC relies on some of these classes, so they are necessary
in Essentials for now. We can explore how to remove them at a later date

src/PepperDash.Essentials.Core/Room/Config/EssentialsPresentationPropertiesConfig.cs

@@ -0,0 +1,22 @@
+using System.Collections.Generic;
+
+namespace PDT.Plugins.Essentials.Rooms.Config
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    public class EssentialsPresentationRoomPropertiesConfig : EssentialsRoomPropertiesConfig
+    {
+        public string DefaultAudioBehavior { get; set; }
+        public string DefaultAudioKey { get; set; }
+        public string DefaultVideoBehavior { get; set; }
+        public List<string> DisplayKeys { get; set; }
+        public string SourceListKey { get; set; }
+        public bool HasDsp { get; set; }
+
+        public EssentialsPresentationRoomPropertiesConfig()
+        {
+            DisplayKeys = new List<string>();
+        }
+    }
+}