You can refuel ships while inside of them

## Reproduction:

Start fueling a ship, use your other hand to enter the ship. The ship keeps getting refueled.

No files, tests, or entry points are named. First reproduce the reported sequence: begin fueling a ship, enter it with the other hand, and check whether fueling continues; trace the fueling and ship-entry behavior, then verify that fueling stops when the ship is entered.

Written by the indexing model from the issue text.