Units::assignTrainer should allow domesticated units

[Hiranus]

https://github.com/DFHack/dfhack/blob/5b5a1ac363d83615584caa37535e943679a2b0b8/library/modules/Units.cpp#L509

Animal can also get trainer in vanilla UI when it is (fully) tamed and player tries to war/hunt train it. For whatever reason you just need to reopen UI for trainer info to appear.

[Hiranus]

I tried to achieve similar result in LUA to be able to train animals from unit overlay but for some reason it didn't work, so it would be good to check if it really works for tamed animals.

function set_training(training,option)
    local unit = dfhack.gui.getSelectedUnit(true)
    if not unit then return end
    local assignments = df.global.plotinfo.training.training_assignments
    local animal_assignment = nil
    for i = 0, #assignments-1 do
        if assignments[i].animal_id == unit.id then
            animal_assignment = assignments[i]
            break
        end
    end
    print(animal_assignment ~= nil ,dfhack.units.isMarkedForTraining(unit))
    if animal_assignment ~= nil and not dfhack.units.isMarkedForTraining(unit) then
        dfhack.units.unassignTrainer(unit)
        animal_assignment = nil
    end
    print(animal_assignment ~= nil)
    if animal_assignment ~= nil then
        print("altering")
        animal_assignment.flags[training] = option
        return
    end
    print("adding")
    animal_assignment = df.new(df.training_assignment)
    animal_assignment.animal_id = unit.id
    animal_assignment.flags.any_trainer = true
    animal_assignment.flags[training] = option
    assignments:insert('#',animal_assignment)
end

[Hiranus]

https://github.com/DFHack/dfhack/blob/5b5a1ac363d83615584caa37535e943679a2b0b8/library/modules/Units.cpp#L418 https://github.com/DFHack/dfhack/blob/5b5a1ac363d83615584caa37535e943679a2b0b8/library/modules/Units.cpp#L426 These two lines should also check if animal is already trained with either war or hunt. Vanilla UI does not allow for retraining of the same animal multiple times, it can only be done once. Also, only adult animals can be trained.