move VoidCallback typedef to APIBoundaryTypes (now used outside the render thread header for texture upload callbacks)

thermion_dart/native/include/c_api/APIBoundaryTypes.h

@@ -10,6 +10,8 @@ extern "C"
 
 #include "APIExport.h"
 
+	typedef void (*VoidCallback)(int32_t requestId);
+	
 	typedef int32_t EntityId;
 	typedef struct TCamera TCamera;
 	typedef struct TEngine TEngine;