The classic response to this , of course, is that you had better submit a "bug report", then! , but I know that isn't really helpful. 😉
The worry with a flying ant is that it might be a "queen' looking for a place to start a colony, though it was more likely just attracted by the warmth. If the computer was running at the time it may simply have been blown back out again, as the vents go to the outlet for the two fans. If it hasn't got too far in you might even be able to blow it out, or encourage it to leave , by putting the computer under maximum stress by running some video rendering or the like. The processor heat sinks end up near the fans , and the beastie might decide that it is too hot for comfort, or get ejected forcibly as the fan speed increases.
Barring that, it is a trip to the repair shop, I fear. I wouldn't really be worried about the likelihood of damage from a single ant, but a pregnant female could do some real harm, once there were a few thousand of her progeny wandering around inside!
You aren't alone, I'm afraid, and
ants really can be an issue in electrical gear, so it needs watching, though the chances are, if there was just one, nothing will come of it.
Good luck!
Rod