Initial commit: Item Interaction Ecosystem plugin (UE5.7)

Server-authoritative, data-driven item/inventory/interaction/carry/equipment/
world-slot/placement/crafting framework. 8 modules, compiles against UE 5.7.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Source/ItemCore/ItemCore.Build.cs

@@ -0,0 +1,25 @@
+// Copyright ExByte Studios. Item Interaction Ecosystem.
+
+using UnrealBuildTool;
+
+public class ItemCore : ModuleRules
+{
+	public ItemCore(ReadOnlyTargetRules Target) : base(Target)
+	{
+		PCHUsage = PCHUsageMode.UseExplicitOrSharedPCHs;
+		IWYUSupport = IWYUSupport.Full;
+
+		PublicDependencyModuleNames.AddRange(new string[]
+		{
+			"Core",
+			"CoreUObject",
+			"Engine",
+			"GameplayTags",
+			"NetCore"
+		});
+
+		PrivateDependencyModuleNames.AddRange(new string[]
+		{
+		});
+	}
+}