feat: web dashboard and playground work

The NexusDashboard-parity dashboard (dDashboardServer) and everything built on it on the experimental branch:
accounts, characters, properties and moderation tools, permissions shared with in-game slash commands, economy
reports, World 3D and property 3D views with client scenery, scheduled events (features, vanity changes, live
events, announcements, restarts), vanity files and events, the CDClient browser, the message inspector with saved
captures, chat filter tools, community challenges, live ops, the AI moderator helper, and the server-side changes
they need.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dGame/dUtilities/ObjectIDManager.h

@@ -5,7 +5,11 @@
 #include <vector>
 #include <stdint.h>
 
+#include "dCommonVars.h"
+
 /**
+ *  Also built into the DashboardServer, which adds items and models the same way.
+ *
  *  There are 2 types of IDs:
  *  Persistent IDs - These are used for anything that needs to be persist between worlds.
  *  Ephemeral IDs - These are used for any objects that only need to be unique for this world session.
@@ -20,6 +24,18 @@ namespace ObjectIDManager {
 	 */
 	uint64_t GetPersistentID();
 
+	struct ModelIDs {
+		LWOOBJID modelID = LWOOBJID_EMPTY;
+		LWOOBJID blueprintID = LWOOBJID_EMPTY; // the UGC model's ID
+	};
+
+	/**
+	 * @brief Persistent IDs for a new player-built model, retrying past IDs already in use.
+	 *
+	 * @return ModelIDs The placed model's ID and its blueprint's ID.
+	 */
+	ModelIDs GetNewModelIDs();
+
 	/**
 	 * @brief Generates an ephemeral object ID for non-persistent objects.
 	 *