What to do if my advisor insists on early attendance?
As a fellow night owl, I feel your pain. Normally I would suggest concisely explaining your difficulties and suggesting a work-around to your advisor, but it sounds like you've already done that. Sadly, your advisor does have the right to set working hours, so you have no real recourse other than finding a different advisor. 

The situation might be different if you have a medical diagnosis/disability -- but I don't think "night owl" will qualify, since waking up early is not harmful to your health (not sure about French law though). What I've done in similar situations is to use melatonin to fall asleep early and caffeine pills to wake up -- probably not the healthiest solution long-term, but it does the trick for me.