Playing cards have a `suit` such as `hearts`/`diamonds`, not a
`type`. Make the internal naming consistent with the way playing cards
are typically named.
`CharacterBitmap` instances are generated at run-time and put on the
heap, but they can be created in a `constexpr` context and stored in
static memory.
Also, remove additional `width` and `height` `static` values in favor
of using the `constexpr` member functions of `CharacterBitmap`.
These changes also include the removal of some initialization code
which tests if the `CharacterBitmap` is created since it is always
created and removes function-local `static` values which cause
run-time branches to ensure it is initialized each time the function
is called.
Now that the cards have rounded corners, draw the stack box behind the
cards with rounded corners as well. This way, the corner of the stack
box doesn't peek out from behind the cards.
The caveat here is that the "play" card stack now needs to hold a
reference to the "waste" stack beneath it so it knows when not to draw
its background on top of the waste stack. To faciliate that, the array
of card stacks is now a NonnullRefPtrVector so the play stack can store
a smart pointer to the waste stack (instead of a raw pointer or
reference).
