As you said, luminosity increases. It isn't a matter of survival, it's a physics problem. If a planet absorbs more energy from its star than it's capable of radiating away, it will rise in temperature forever until and unless energy output increases above energy input.

And when you consider that by this point energy input is on a permanent increase, there's really not much you can do apart from moving the whole damn planet out of the way.

It's kind of pointless to speculate what kind of technology we'll have in 500m years (or indeed if there is a 'we' left in the system). The time scale is so enormous that there's simply no way to predict anything at all involving humans or human-derivatives.

The planet (without literally unimaginable intervention) will heat up and become uninhabitable sometime around 500m years from now.