We've had our Model S for a week now, and this might be a stupid question, but here's the scenario: Let's say we're in Phoenix in the heat of summer, and I drive my grandma to the store. She wants to stay in the car in the air conditioning while I run in and grab a few things. I leave the key in the car, but when I jump out the car shuts down, turning off the climate. Grandma's dead in 5 minutes! So, how do I 'run in to the store' while leaving the air conditioning running for somebody who wants to wait behind in the car? I hope I don't have to do that with the app, because that's kind of a pain.