Add server/client annotations to settingtypes.txt and make use of them (#15756)

src/script/lua_api/l_pause_menu.h

@@ -11,6 +11,7 @@ class ModApiPauseMenu: public ModApiBase
 private:
 	static int l_show_keys_menu(lua_State *L);
 	static int l_show_touchscreen_layout(lua_State *L);
+	static int l_is_internal_server(lua_State *L);
 
 public:
 	static void Initialize(lua_State *L, int top);