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/ItemInteraction/Public/InteractionTraceComponent.h

@@ -0,0 +1,60 @@
+// Copyright ExByte Studios. Item Interaction Ecosystem.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "Components/ActorComponent.h"
+#include "InteractionTraceComponent.generated.h"
+
+class UInteractableComponent;
+
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_TwoParams(FOnInteractionTargetChanged, AActor*, NewTarget, UInteractableComponent*, NewInteractable);
+
+/**
+ * Local-only aim trace that finds the best interactable under the crosshair
+ * (section 8.2). Runs only on the owning client; the result drives the prompt UI
+ * and is what the player confirms - never trusted by the server.
+ */
+UCLASS(ClassGroup = (Interaction), meta = (BlueprintSpawnableComponent))
+class ITEMINTERACTION_API UInteractionTraceComponent : public UActorComponent
+{
+	GENERATED_BODY()
+
+public:
+	UInteractionTraceComponent();
+
+	virtual void TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction) override;
+
+	/** Fires the trace once and updates CurrentTarget. */
+	UFUNCTION(BlueprintCallable, Category = "Interaction")
+	void TickTrace();
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Interaction")
+	float TraceDistance = 300.f;
+
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Interaction")
+	float TraceRadius = 12.f;
+
+	/** Trace channel; defaults to Visibility. */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Interaction")
+	TEnumAsByte<ECollisionChannel> TraceChannel = ECC_Visibility;
+
+	UPROPERTY(BlueprintReadOnly, Category = "Interaction")
+	TObjectPtr<AActor> CurrentTarget = nullptr;
+
+	UPROPERTY(BlueprintReadOnly, Category = "Interaction")
+	TObjectPtr<UInteractableComponent> CurrentInteractable = nullptr;
+
+	UPROPERTY(BlueprintReadOnly, Category = "Interaction")
+	FVector LastHitLocation = FVector::ZeroVector;
+
+	UPROPERTY(BlueprintReadOnly, Category = "Interaction")
+	FVector LastHitNormal = FVector::ZeroVector;
+
+	UPROPERTY(BlueprintAssignable, Category = "Interaction")
+	FOnInteractionTargetChanged OnTargetChanged;
+
+private:
+	bool GetViewPoint(FVector& OutLocation, FRotator& OutRotation) const;
+	void SetTarget(AActor* NewTarget, UInteractableComponent* NewInteractable);
+};