Fix the room code field and give the multiplayer screen a close control

- The room code field was a 94px box with a clipped placeholder: twice the
  height of the name field above it, and the largest control on the screen
  for the smallest input on it. align-items: stretch was inflating it from a
  natural 46px, and the field was sized to whatever width was going rather
  than to the five characters a code actually is. It is now 9ch wide and
  matches the height of the Join button beside it, which is sized to match it
  in turn rather than being a full-size action.
- The multiplayer screen was the only one reachable from the rails without a
  close control. Both of its views have one now.

0 files changed, 0 insertions, 0 deletions