* MangaScreen: Improve chapter list scrolling performance
Process chapter title, date and read progress string ahead of time
* Use enum for contentType and add key
* Increased touch target
* Fix downloaded icon smaller than other states
* Deferred state reads to minimize recompose works
* Move things around to eliminate unnecessary elements
Animating the content padding that's used for the lazy list is heavy. A simple
fix to *just* offset the list is blocked by a Compose fling issue (b/179417109).
So I decided to go with the previous layout of this screen by putting everything
in the list. MangaInfoHeader is split into separate composables to avoid jank
when the item is being inflated.
