I always pull forward, wave to the flaggers, smile, say "thank you" when they tell me to go, sometimes talk to them, etc.
They certainly aren't my adversary.
The construction zones are an annoying pinch area where cars can't easily pass bikes, so for many cyclists, a sidewalk might be preferable. I usually sprint as fast as I can to get through the areas keeping up with traffic the best I can.
On occasion I've seen signs directing bikes onto the sidewalks which I'll generally do.
A couple of years ago one of the main arterials was closed. I could have gotten around it but it would have added perhaps 2 miles to the ride, including 1 mile on the freeway.
The flaggers seemed to recognize that it was a pain in the rear, and just told me to go ahead and avoid the construction equipment. Overall it wasn't bad, and had the advantage of reducing traffic for most of the rest of the ride.
I do find it annoying when bike lanes are blocked for no apparent reason, or the construction workers seem to think that putting a sign in the middle of the bike lane is the best place to put it.