Thatcham approval counts for a lot in the security industry - not a cheap option but neither is your motor...
https://www.carnoisseur.com/products/details/disklok-steering-wheel-lock?gclid=EAIaIQobChMI2d-17dP12AIVbbXtCh1KsAEwEAkYASABEgJmE_D_BwE
DPF regeneration. Should not start stop when it is active. You will notice that when the car is cleaning the DPF that the tickover speed is higher - mine sits at 1000 instead of 800 RPM.