What a lovely and supportive friend!
I would say it is always good for someone else to also be on top of when to take any meds - I had no idea when I had taken the last set, but my DH was v on top of that which really helped. When painkillers wear off and you have forgotten to take the next set - it isn't great! Especially in the early days!
Bathing can be tricky - getting in and out of the shower or just feeling a bit wobbly afterwards - not that I am suggesting you should help with the shower bit, but making sure she rests afterwards will help.
Helping with yummy, vitamin filled food etc will be a godsend. Hospital food is rank. How anyone is meant to recover with the aid of that stuff is beyond me.
She may want to talk about the experience so being a good listener may also help if you feel you can do that.
Generally someone clucking over you can either be lovely or v irritating, so asking her what she would like you to help with I'm sure will be hugely appreciated.
My mum set up a little station next to the sofa, baby things that will be needed to hand, a little side table for drinks etc so when I was resting I didn't have to keep moving.
Oh and when I came home my DH had bought some lovely cheery flowers which were beautiful to look at after being in a dreary hospital environment. That was when I wasn't baby gazing ;-).
Very lovely of you to be thinking of how to help her out :-)