Tums flavors may not appeal, but you can cut in half and just plop it ito the back of her beak. It might be hidden into some yummy treat such as eggs, but giving it straight up, you know that she got it. Still sitting on the nest is a little worrisome that she may be going to pass more egg material, or that she feels very poorly which does happen with these temporary problems. Hopefully she will feel better tomorrow, but I would offer some water or electrolytes if she will drink. Most hens will eat crushed egg shells that have been saved and crushed, and those have calcium.