[Protocol] Share tournament messages and report draws explicitly

- TournamentPlayer/TournamentPairing/TournamentSettings move into
  serverinfo_tournament.proto, imported by both the tournament event and
  the tournament game commands, so Command_CreateGame reaches them without
  crossing the command/event boundary
- Command_CreateGame carries the full TournamentSettings instead of a
  duplicate games_per_match field, keeping game creation and mid-game
  changes on one wire representation
- draw results are explicit: Command_ReportMatchResult and
  TournamentPairing gain is_draw, so a report stays distinguishable from
  an unset -1 winner
- pairing match-wins are uint32 like the other game counts

libcockatrice_protocol/libcockatrice/protocol/pb/event_tournament_state.proto

@@ -1,27 +1,6 @@
 syntax = "proto2";
 import "game_event.proto";
-
-message TournamentPlayer {
-    optional sint32 player_id = 1;
-    optional string player_name = 2;
-    optional uint32 wins = 3;
-    optional uint32 losses = 4;
-    optional uint32 draws = 5;
-    optional bool deck_submitted = 6;
-}
-
-message TournamentPairing {
-    optional sint32 player1_id = 1;
-    optional sint32 player2_id = 2 [default = -1];
-    optional sint32 game_id = 3;
-    optional sint32 winner_id = 4 [default = -1];
-    optional sint32 player1_match_wins = 5 [default = 0];
-    optional sint32 player2_match_wins = 6 [default = 0];
-}
-
-message TournamentSettings {
-    optional uint32 games_per_match = 1 [default = 1];
-}
+import "serverinfo_tournament.proto";
 
 message Event_TournamentState {
     extend GameEvent {
@@ -40,4 +19,4 @@ message Event_TournamentState {
     repeated TournamentPlayer players = 4;
     repeated TournamentPairing pairings = 5;
     optional TournamentSettings settings = 6;
-}
+}