Add support for up to 6 players.

internal/game/game_test.go

@@ -33,8 +33,16 @@ func TestLobbyManualStart(t *testing.T) {
 	if _, err := g.AddPlayer("Bob"); err != nil {
 		t.Fatal(err)
 	}
-	if _, err := g.AddPlayer("Carol"); err == nil {
-		t.Fatal("third player should be rejected while MaxPlayers=2")
+	// An odd table can't pair off, so a third player has to be matched by a
+	// fourth (or removed) before the host can start.
+	if _, err := g.AddPlayer("Carol"); err != nil {
+		t.Fatal(err)
+	}
+	if err := g.StartGame(); err == nil {
+		t.Fatal("start should be rejected with an odd number of players")
+	}
+	if err := g.RemovePlayer(g.Players[2].ID); err != nil {
+		t.Fatal(err)
 	}
 	// The lobby stays open until the host explicitly starts.
 	if g.Phase != PhaseLobby {
@@ -503,11 +511,11 @@ func TestFullGameFlow(t *testing.T) {
 		if g.Phase != PhaseBattle {
 			t.Fatalf("expected battle after both arrange, got %s", g.Phase)
 		}
-		if g.Battle.WinnerSeat != p1.Seat {
+		if g.Battles[0].WinnerSeat != p1.Seat {
 			t.Fatalf("round %d: seat 0 should win", round)
 		}
 		// The winner hands the token to the loser; a loser keeps it.
-		if wantPriority == g.Battle.WinnerSeat {
+		if wantPriority == g.Battles[0].WinnerSeat {
 			wantPriority = (wantPriority + 1) % len(g.Players)
 		}
 		for _, p := range g.Players {