Rewrite diplomatic tribute code in its own file.
The rewrite is more react-ive by definition - as in like React - as in I separated state and rendering, when they were tied before.
If we rewrote every input mode like this, the input.js could be genericised, and then we wouldn't even need D1786.
Open questions:
- Should we create the object when opening the diplomacy window?
- How much do we want to automate the reactivity of rendering?