Sizing a landscape lighting transformer
How do you calculate the current draw of the lights plus the resistance of the wire to determine the required transformer size?

You do not need to
At that low of a current draw voltage loss will be negligible. The big concern about voltage loss with outdoor lighting was important with incandescent and halogen bulbs, not LED.
The calculator I used would put end-of-line voltage at 11.59 in your setup. Your LED bulbs will operate correctly down to minimum voltage required to power the fixture. Typically anything higher than 8.5 volts is acceptable; check your specific fixture.