It's kind of weird that the stars are so visible when the Erdtree's glowing so bright but that seems like the kind of thing you're not supposed to think about too hard.

Eventually she starts reading a textbook for lack of anything better to do.

She's four chapters in before she realizes that it should really feel like lunch at this point, and being stressed out from the spontaneous teleportation accident explains some delay but not four chapters' worth. Maybe it's one of those times where she'll be abruptly ravenous if she takes one bite.

She'll step into the hall to look for a page.

There's a man sitting in the hallway, with fine but not extravagant clothing. 

"Do you need anything, milady?"

"I was starting to wonder about getting something to eat?"

"Of course. What do you desire to eat?"

"...I don't know what you have here. I'm not picky. If you're going to pull exactly whatever I suggest out of a magic kitchen appliance I guess I want a roast beef sandwich with pickles."

"I'll see to it."

He leaves, and comes back after a short while. 'sandwich' part is clearly improvised, but it is as requested. 

"Thanks."

She retreats to her room to eat her sandwich.

It's a sandwich, in a sense that it's roast beef put between pieces of bread, but it's clear that the components weren't originally made to go together. It's good though.

She doesn't become ravenous when she takes a bite but she can chomp her way through the sandwich on general principle and then go back to reading by the window.

Eventually, the sun rises over the horizon. The stars fade away, but not completely, still slightly visible even in daytime. The dark moon hangs there, stationary. 

She's not really tired, it's probably not bedtime yet in her time zone, but when she notices the sun coming up she'll pull the curtains shut and try to sleep to get closer on that front. For all the copious socializing she's doing. Yeah.