A fairly large change that replaces Zaps in the codebase with "Zapping"
which is a tagged union consisting of a resolved Zap and a Pending Zap.
These are both counted as Zaps everywhere in Damus, except pending zaps
can be cancelled (most of the time).
Changelog-Added: Added event preloading when scrolling
Changelog-Added: Preload images so they don't pop in
Changelog-Fixed: Fixed preview elements popping in
Changelog-Changed: Cached various UI elements so its not as laggy
Changelog-Fixed: Fixed glitchy preview
