Can I suspend lights within my property boundaries, above my wall heights on my roof deck?
IANACO  (I am not a condo owner)  

This seems like something that won't be in the rules because no one thought it important.  Probably no rule about using your deck for landing starship shuttles either.  Same idea.

That said.  Simple courtesy requires that you not disturb the other owners. So...

A:  Wire it up with a 3 way switch with a switch on each neighbor's fence.  This would allow them to turn it off if they have a stargazing party and you forgot to turn the lights off.

B:  Get/Make lamp shades that reflect the light that would otherwise go onto your neighbours place.  Boundary lights have a triangle (actually a parabola shape) that is white on  your side, some innocuous colour on your neighbors side that reflects light back onto your land.  Lights inside the boundary wear a cone to direct the light in a cone that doesn't go over the fence.

Depending on how fractious your condo association is, you may want to ask first.  Sketch out what you propose to do and ask your two neighbours if this is a problem. 

As a neighbor I would usually be more concerned about noise than about light.