Dynamic UI + Buttons

- “UI” elements position themselves dynamically based on the size of
the screen/camera.
- “I’m avoiding using the GUI layer, what I’ve made seems easier to
work with and light enough to not hurt performance.
- Implemented a button system with placeholders for both an
inventory/menu button (left corner) and an action button (right corner).
- inventory button brings up placeholder inventory/menu
- started work on a dynamic star generator that will only instantiate
stars at the edge of the screen, and destroy them when they are out of
view. (should save a ton on performance!)