Fix HITMAN 3 boot, layered presentation, and socket imports (#851)

* videoout: synchronize layered flips with premultiplied composition

* shader: support unsigned FFBH subword sources

* shader: apply cube-face result scaling

* shader: prune buffer reads proven out of bounds

* net: implement send and receive exports with shared socket handling

---------

Co-authored-by: nmzik <Nmzik@mail.ru>

src/graphics/presentation/presenter.h

@@ -4,6 +4,7 @@
 #include "common/common.h"
 
 #include <memory>
+#include <span>
 
 namespace Libs::Graphics {
 
@@ -15,6 +16,11 @@ struct WindowContext;
 class Presenter final {
 public:
 	struct Frame;
+	struct Layer {
+		Frame* frame;
+		int    bus;
+		bool   premultiplied_alpha;
+	};
 
 	explicit Presenter(WindowContext& window);
 	~Presenter();
@@ -23,11 +29,13 @@ public:
 	[[nodiscard]] Frame&         PrepareFrame(CommandBuffer& command, const ImageInfo& info);
 	[[nodiscard]] Frame&         PrepareBlankFrame(uint32_t width, uint32_t height, bool opaque,
 	                                               CommandBuffer* producer = nullptr);
-	[[nodiscard]] Frame*         PrepareLastFrame();
+	[[nodiscard]] bool           PresentLastFrame();
 	[[nodiscard]] bool           IsGuestPaused() const noexcept;
 	[[nodiscard]] bool           NeedsSystemOverlayRefresh() const noexcept;
 	[[nodiscard]] RenderContext& Renderer() const noexcept;
-	void                         Present(Frame& frame, bool reuse = false);
+	void                         Present(Frame& frame);
+	void                         Present(std::span<const Layer> layers);
+	void                         ClearLayer(int bus);
 	void                         Discard(Frame& frame);
 
 private: