Would it be realistic to live in an airplane?
Sure, it actually is more common than you might think. While the general notion of a private plane is a small sleek jet to dart about in, plenty of wealthily people own larger jets equipped as you describe. Nick Gleis is somewhat famous for photographing the biggest of the biggest private jets and this article covers a lot of the really cool stuff he has seen.
The FAA does not necessarily mind how you configure interiors as long as you don't try and qualify things as a &quot;seat&quot; for occupancy, takeoff and landing purposes.
Sleeping on the apron is likely more about airport rules than anything else. You would need some kind of an APU to run your electronics as most airports wont want you running your engines all night...
If it does not need to fly this is always an option.
While you likely cant order the cool defense stuff there is nothing stopping you from outfitting a VC-25 similar to Airforce One which is more than livable.