Building a 12x12 shed on concrete slab. It will be livable; mini-split, electric, insulation, etc.

I'm having a tough time sourcing the door. I'd like a double (french) door, fiberglass, no window. It will receive some shrapnel from the lawn mower and I don't want to break any glass.

Home depot will put one together for me, but the reviews on Masonite aren't great.

Any bullet-proof, quality door companies out there I can order from online? The whole thing is daunting.

It's a misconception that French doors are double doors. This isn't the case. A French door is one in which the panels are mostly glass. Single, double, triple, is irrelevant. You want a 6-0x6-8 double exterior door. I don't see a normal glass window being an issue (not sure what you mean by shrapnel), but it's your door. I'd go to a lumber yard for this item.

Also, have you thought of making one? A frame kit, 2 slabs/cores, and some hardware.