Implement vector and node conversion in Lua (#12609)

Co-authored-by: sfan5 <sfan5@live.de>

src/script/lua_api/l_item.h

@@ -174,4 +174,5 @@ class ModApiItemMod : public ModApiBase {
 public:
 	static void Initialize(lua_State *L, int top);
 	static void InitializeAsync(lua_State *L, int top);
+	static void InitializeClient(lua_State *L, int top);
 };