Re animals near food outlets. Its quite usual here, for pubs to have pets corners, with pigs, goats, lambs, hens etc. and all those pubs serve meals. Its not as though they are inside the buildings is it, so surely thats ok?
I had the neighbours from hell at my last place, and I vowed I would never again live next door to anyone. They made my life a misery, complaining to the council constantly about us. And the council admitted the neighbours did not have a valid complaint, but they still had to follow it up. In fact one of the council people suggested my neighbour was "unstable"!!!! So many people are in the same position as you, James. Its all fine, then suddenly an issue arises and things turn nasty.
I would do whatever it takes to get this sorted now. You want peace of mind, not years of legal battling. Do hope you get sorted, and peace is restored.