There will certainly be something that suits those needs. You can get a hybrid/CX style bike with disc brakes, aluminum frame and carbon fork. The trick will be finding one with a triple. Usually bikes with triples are on the lower end and tend to have rim brakes. If she/you can live with either a compact double or rim brakes, there's a ton of choices out there. Let me tell you, for a couple years I really wanted a road bike with disc brakes, and now that I have one with disc brakes and another with canti brakes and good pads, I really couldn't care less.
Some of the Trek FX series bikes fit all your needs and come with 32mm tires, you could likely go a bit larger: FX - Trek Bicycle
My recommendation would be get one with a double chainring and get a little bigger cassette.
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