The main realization came when I figured out that the main_model was just another association. This means we can move a lot of logic to just that class and reason about it a lot better.

Got a bit sidetracked into refactoring the Element visitor code, so haven't actually started on the event handler stuff per se, but that'll come soon. Element stuff is starting to feel a bit more logical and easier to follow.

Svelte slots are much easier to use and reason about than Angular transclude, especially in cases where you don't want an extra wrapper element around the slot content.