[Feature] Create home screen ui

Currently the game has no homepage with ui.

I don't really have a clear idea of how to do this, but I have some general points:

* It would be good if we could seperate the game loop into another file `gameLoop.ts`.
* Use react for the ui.
* Create `HomePage.tsx` to contain ui components. There should be a play, options and github source button present.
* Add state management to the entry file `main.ts` such that it initially directs to homepage then to gameplay once the play button is pressed.