Add Multiplayer Setup & Game Lobby to Main Menu #301
Description
- Add sign-in/sign-up screen #329
- Add game listing screen #330
- Make game listing scrollable #325
- Multiplayer: Add game creation #326
- Implement in-game screen (before game starts) #327
- Multiplayer game initiation #328
- Handle already in a game state after sign in #383
- Lobby: Disable join game button if the game is full #395
Relates to #255.