If the mineral oil or hydraulic brake fluid gets on the pads, they should replace the pads. If it gets on the rotor or anything else, they should clean it thoroughly with isopropanol. If it leaked brake fluid (not oil), then a coupling needs to be adjusted or replaced. The main thing is they should provide you with a bike whose brakes work. If not, it is defective, and they need to either make it right or give you your money back.

My rear Shimano hydraulic Ultegra caliper failed a few months after I got my bike. Shimano warrantied it. Shyte happens, but give them a chance to make it right.

Bleeding a brake is something you do to change contaminated hydraulic fluid and/or get rid of air bubbles. If there was a leak, they will need to bleed it, because if fluid got out, air got in, ipso facto. You should never see brake fluid leak from anything if the brake is working properly. If it is leaking, it can fail catastrophically, especially if it is the front brake.