Restrict trained animals to a zone

[kd8lvt]

Problem description
I like to set a zone for my hauling-capable animals so that they don't go and try to haul something in the middle of a raid or in an otherwise inhospitable environment I'd rather colonists deal with. The problem with doing this with Manager is either you set all the animals of a type to be in a zone or you set none of them, and I like to do a mix, for flavour.

Describe the solution
The idea is, under the "Livestock" jobs, under and similar to the "Restrict animals marked for training" there would be a "Restrict fully trained animals" panel. It'd work functionally identical, apart from specifically targeting animals whose training is finished, rather than ones marked for training.

Alternatives
I've considered making it a separate mod, but I think if it were, it would probably conflict with restricting to zones in Manager, which would be an issue... and also I'm terrible at making GUIs.

Additional materials
Nothing from me, I'm an ideas and code guy, not a designer, unfortunately. Can't have it all, as they say.