How do you come to a stop without dismounting?
Ultimately it comes down to balance, what you have to work out is whether you can balance easier while moving slowly or not.

Watch a few track stand videos to see whether you think it's possible, if your sense of balance is good it's possible on any bike.

All that's required is generally a few inches of movement while braking and leaning into the direction required.

Some other alternatives if you really can't track stand would be : 

Anticipate the lights changing so you don't have to stop, this will require slowing down but you shouldn't have to actually stop.

Or stop a few metres short of the lights so you have minimal time to track stand and have space to creep forward. 

I don't know what the roads are like where you are but if there's a rail or post next to the lights you have the option of leaning on them and pushing off when the lights change.