Adds the protocol layer for the tournament game mode:
- Event_TournamentState (2027) carrying phase, round counters, player
standings, pairings, and settings (games_per_match)
- Command_ReportMatchResult / Command_AdvanceTournament /
Command_TournamentSettingsSelect game command extensions (1037-1039)
- is_tournament flag on Command_CreateGame and ServerInfo_Game;
is_tournament and parent_game_id on Event_GameStateChanged
Took 13 minutes
