Train refueling issue

Issue description

Trains will not stop at a scheduled station to refuel if they do not load or unload at it.

Reproduction steps

Build a train loop for two stations with a refule point.
Build a second loop with two stations without a refuel point but pass it through the station with the refule point in the first loop.
Watch the trains fail to stop at the station despite it being set as a stop and run out of fuel.

Game version and build number

v0.7.8a b486

Operating system

Windows

Attachments

Save file: https://gofile.io/d/GiSi6E

Watch the train on the sand line.

This is working as intended - you have "only when on low fuel" set. Trains visit it if they depart their last schedule item with <30% fuel. They drive through if not. The full loop of the schedule is pretty much all the fuel for this train (single steam loco with no tender) so this often causes issues as they can leave the last station with 40% fuel and run out well before they return to it.

In this case the station is on their route anyway, so they appear to drive through it with very low fuel.

Solution here is not the use the "only visit if low on fuel" button for lines which need almost all the train's fuel to do a full loop.

This is a recurrent problem in the game of the option saying one thing and what it actually does being something different. It is extremely irritating.

Is it your intention to annoy people with your game?

Please change "stops to refule when <30%" to "stops to refule when leaving previous station at <30%" That way the user would be clued into the nature of the issue and not have to post a bug report.

Will it be better to add separate "refuel stations" list, to train to to refuel when fuel reaches 30%, not when departing with 30%? I often get trains stuck with "no fuel" right before refueling station, while going to refuel?

Also, an option to make some task to be executed "only if cargo contains X" will be useful (and to be skipped otherwise, like refuel option do)