New front and rear disc pads installed. Brakes groaning when almost stopped and when released.
Sounds like the rotors were not resurfaced or replaced.
Could be that the pads were installed without shims or the mechanic did not dab grease on the contact points where the pad meets the caliper. Hard to know without hearing the noise.
Maybe the calipers are not on the pins, I have had a couple shops not do that and brakes had to be redone by someone that knows what they’re doing. When they don’t this correctly one side of caliper always drags and can potentially ruin the new pads and rotors.
It might go away. It might not. It is annoying but unlikely to hinder stopping much like squealing brakes.
Some combinations of pads rotors and cars have these problems, especially if the rotors were not replaced, turned or turned badly.
Another possibility is that the groaning may be caused by the sway bar bushings. Rubber hardens after a while and can bind on the sway bar.
You might try pushing down repeatedly on the front suspension while listening for any noises. If that is the cause then some aerosol lubricant might shut it up rather than replace the bushings.