kobako-wasmtime

https://github.com/elct9620/kobako

A name reservation, not a runtime. kobako's wasmtime driver still ships inside the kobako gem, so installing this one adds nothing and requiring it raises. Install kobako instead: https://rubygems.org/gems/kobako Moving that seam — so which driver gem you install is the choice of engine — is planned in https://github.com/elct9620/kobako/issues/76, and the name is held for it.