Coffee (along with all caffeinated beverages) is a diuretic so in the light-speed fast GI tract of a parrot, it could yield a watery poo as it moves through faster than normal and encourages the body to pass more water. Parrots should have no tolerance built to the diuretic effects of caffeine so it will be more pronounced than in a human who drinks coffee every day and who's body is used to it. Shouldn't be more than a couple poos though, unless she has had a lot of other moisture rich food today or a bath. I might not give her either of those today if you haven't already just to be able to monitor things.
All creatures need a certain amount of salt in the diet. It's the excessive salt thats an issue. I use my fingers as guides for portion sizes of foods Kiwi really shouldn't have

Human foods not specifically prepared for him like beans, rice, pasta, bread, grains, cereals etc..., he gets about the size of my thumb portion wise. Things like peanut butter, sweets, cheese etc.. he only gets about the size of the tip of my pinky. A little human food is ok for parrots eating a healthy diet rich in fresh foods, but if the bird is a picky eater, not eating much fruit or veg, still on a seed diet etc... should get no human food at all. Exceptions would be things prepared especially for the bird without added salt or added sugar, such as plain rice, plain pasta, plain beans, plain grains etc... all are very nutritious and can be fed openly so long as you don't add salt or sugar or anything else of questionability to them.