vehicle.trainPosition is only synced when it has an occupant

[ArranTuna]

Describe the bug

@qaisjp said:

This only affects the server.

There isn't any desync with the actual vehicle.position. This also has the added affect of the trainPosition being 0 (default position) until it has been entered.

Entering the train will update the train position server side. If you leave the vehicle the trainPosition will no longer be updated

To reproduce

run v = Vehicle(449, getRandomPlayer().position)
run v.id = "test"
run v.trainPosition -- will return 0
crun Element.getByID("test").trainPosition -- will return non-zero value

Additional context
From https://bugs.mtasa.com/view.php?id=9305

[Cazomino05]

most likely just some missing sync for trainPosition. I can't imagine this is difficult to fix if the vehicle is in range of someone to sync it, when I left off train sync I did consider that this is VERY easily calculated since it's just time/distance calculations and there is really no reason why a very simple "emulator" couldn't be implemented here in the server.

[ModafinilCPP]

any solution for this?