I had an ED at around her age, and I tend to agree with her methodology for recovery - back in the 90's my dietician was "Eat whatever, hell, have two cakes, so long as you gain" which really screwed up my association of food for a long, long time (I gained, and more so, which is really common).
If she feels comfortable restricting or avoiding white carbs etc, then that's cool - she can get plenty of calorie heavy, healthy foods such as avocados, nuts, cheeses etc. These are all very well promoted foods within the "health food" industry, so it will pay off making sure she sticks to a sort of unprocessed diet moving forwards.
If she's not keen on white carbs - wholemeal bread, wraps, pittas are a good shout. Same with pasta/rice - quinoa and cous cous etc. Plenty of carb alternatives to white pasta and bread.
Good idea for breakfast would be some wholemeal bread and a couple of scrambled eggs, or a bowl of granola and yoghurt with a banana.
Mid morning snack at school could be a handful of almonds or cashew nuts which are easily transported in a small tupperware box.
Lunch - wrap with chicken, salad and an apple/other fruit. She could also fit in more yoghurt here depending on how her appetite increases.
Home-time - Perhaps this could be scheduled for a "treat" if she feels able in future - a hot chocolate, a flapjack, something she can work towards and feels comfortable doing. For now, carrots with hummous is a good shout, or a selection of veg with a dip (yoghurt, salsa) would be a good, healthy tide over snack (same with crackers and hummous etc).
Dinner - Wholemeal spaghetti with bolognese and lentils, chicken salad with potatoes and avocado, you can even do wholemeal bases for pizzas with plenty of tomato sauce, veggies and a bit of cheese. Baked sweet potatoes/jacket potatoes with tuna.
If she has a particular favourite, hone in on it - if she's used to routine in restricting, having a favourite meal may enable her to feel a semblance of control that she's losing now she's committed to recovering from restricting her diet. May also be worth buying a family whiteboard/chalkboard that can go in the kitchen so she can plan out her weekly meals, for the same reason as above. This means it's visible for you all - if she was to note it down privately she may be incline to write down "xxx = 300 calories" and then total it up - if it's on a chalkboard, she can't easily get away with tracking calories.
There are so many more health products on the market these days catered to those who want to maintain or gain weight carefully - the emphasis has shifted from the "doesn't matter as long as its low fat" culture of the mid-90's and more toward the "sustainable, unprocessed food" culture of raw food diets etc.
I wish you both lots of luck and best wishes for the future. I'm not a health professional, and I'd advise any suggestions I made (esp about writing out food plans etc) be discussed with your professionals as I wouldn't want to contradict their plans. It was just something I felt I would have benefited from in hindsight, but definitely does depend on whether your DD is stable enough to not let any form of control escalate back.