Hi,
I am not aware of any plan officially for TVOS support, but I expect Unity to provide a unified Input system, so it may be that the regular Unity Inputs will work, and so the Input actions will work fine.
as for Apple Watch, there is no support from Unity yet, only some big hacks to make it work. It's on their road map for 2016, until then, unfortunatly, I don't recommand trying to build for apple watch unless you are very fluent with xCode.
Bye,
Jean