I’m no art expert or anything but here’s my view.

1 and 2. Yes. You used tools to create the art, not all that different from using a pencil or paintbrush, or a tablet you didn’t create yourself. It was however your imagination that created it. It wasn’t generated from a couple of sentances, what was created was (depending on skill of couse) what you pictured it should be. You didn’t just generate 1000 possibilities and picked the prettiest one and called it yours.

3. It would still require human imagination to create the art, so I would still deem it art.