fetch glfw only on windows

CMakeLists.txt

@@ -9,8 +9,9 @@ add_executable(VulkanSimulation ${SRC_FILES})
 find_package(Vulkan REQUIRED)
 
 include(deps.cmake)
-
+if (WIN32)
-FetchContent_MakeAvailable(glfw)
+    FetchContent_MakeAvailable(glfw)
+endif ()
 FetchContent_MakeAvailable(glm)
 FetchContent_MakeAvailable(vma)
 FetchContent_MakeAvailable(tetgen)

include/vulkan/buffer.hpp

@@ -5,9 +5,6 @@
 #include "vertex.hpp"
 #include "vk_mem_alloc.h"
 
-class Instance;
-class CommandPool;
-
 class Buffer {
 public:
 	explicit Buffer(VkDeviceSize size, VkBufferUsageFlags bufferUsage,