Store tool handlers as shared pointers

src/station_gui.cpp

@@ -2520,3 +2520,10 @@ void ShowSelectWaypointIfNeeded(TileArea ta, StationPickerCmdProc proc)
 {
 	ShowSelectBaseStationIfNeeded<Waypoint>(ta, std::move(proc));
 }
+
+namespace citymania {
+	void ShowSelectStationWindow(TileArea ta, StationPickerCmdProc&& proc) {
+		if (!_settings_client.gui.persistent_buildingtools) ResetObjectToPlace();
+		new SelectStationWindow<Station>(&_select_station_desc, ta, std::move(proc));
+	}
+}