Hmm.. I think the closest size to the 26.5" is a 24" door. It's small, but manageable. I have a couple of those in my house. If you use a metal channel, make sure it is water/rust resistant.
Looking at the layout again, I realize there would not be a way for the door to swing in to the bathroom bc it would hit the toilet. So, it will have to swing out. When facing the door from the outside of the bathroom, will you have the knob on the right or the left?
If it's on the left if will be a left-hand swing. If the other way it will be right-hand. I'm sort of guessing that it will be on the left because the first thing you would see is the sink instead of the toilet and for some reason, it's not "cool" for the toilet to be the first thing visible when entering a bathroom.
I'm not sure what shaker style is. Something like this?
https://www.homedepot.com/p/Builder...gle-Prehung-Interior-Door-HDCP6620R/202523938
(Assuming your door height is 80"-- should measure that to be certain).
Or this?
https://www.homedepot.com/p/Masonit...-Single-Prehung-Interior-Door-10584/202505856
Or solid core version:
https://www.homedepot.com/p/Masonit...-Single-Prehung-Interior-Door-49157/202872641
I'm no flooring expert, but I wouldn't advise using laminate in a kitchen. It doesn't handle moisture/spills very well. There are probably some that are better than others at resisting water, but for some of them, one little spill and the floor bubbles up. Hot water splashing out of the sink, spilled pot of water/sauce, or leak from under the sink could spell disaster. A friend of mine has laminate throughout her house. Her kid (I think she's 3 or 4) was trying to bring a bowl of soup to her bc she knew she wasn't feeling well. Lost her balance, fell, and spilled it all over the floor. My friend cleaned it up as quickly as she could, but the damage was already done.
Vinyl plank is more expensive, but if you get the kind with plastic/waterproof core and stay away from cork underlayment, it can be pretty good. I see it used in restaurants and department stores now. You can get the click-lock kind that is easier to install. But, it's ultimately up to you.