Implement feature: Automatically configure game mode before starting the round

[Christian-Toney]

As a developer, I want a universal system that automatically initializes game modes and handles game mode initialization errors so that the server gives an expected experience to the players.

Since game modes should be chosen from the lobby, a game mode should be arbitrarily selected as a test to complete this task.

Dependencies

• Design feature: Matches design#101: Required to understand the design intentions of matches/rounds.
• Implement feature: Download and build compatible stages #69: Required to attach the stage to the round information.