I don't have any empirical evidence for you, so this is mostly opinion. IMHO, a supercharger will not change a redline. The redline is a factor of the mechanical abilities of the engine (internal components), and has nothing to do with anything the supercharger does to it (basically adding hp). If you don't change anything internally on the engine (rods, crank, bearing clearances, etc, etc, etc), you won't be changing anything to do with the redline.
With that said, the LS3 (manual) or L99 (auto) engines there are some minor things which you'll need to worry about, but the redline is not one of them. You'd experience valve float (with a stock valve trane) before there'd be an issue which is going to cause you damage to your engine. While valve float is not a good thing, it's not the end of the world.
From what I was just reading, the redline should be 6500rpm and then there's a rev limiter which kicks in at 6600rpm. This means there really should be no issue with over revving, unless your tuner changed these settings. With the correct valve train, guys are revving these past 7000rpm, with forced induction, and a stock bottom end, without issue. The stock bottom ends on these are good to over a 1000hp.
Realize, though, when you put more power through an engine, whether by tuning or by parts, you are going to affect the life of the engine. It will incur more wear and tear. It's just the nature of the business. How much will it shorten it by? I couldn't tell you, as there's no magic formula. On your car, you need to worry about the rear differential and drive axles. These were relatively weak from the factory. They were good for the stock engine, but once you start throwing power at them, you're just begging for it to blow. There are some good kits on the market which are direct replacements which are good for your needs. I'd highly suggest you make this your next mod.