Sane copbot behaviour (fixes #9171)

If the player is cuffed and the police bot doesn't get damaged it will not harm the player. It now makes sense to not resist arrest and just run away after the copbot spawns. Also fixed the glitch with "put down your weapon" message while the 'weapon' is the handcuffs.

Tried a number of different approaches and this seems to have the best balance of sanity vs. code complexity.