Add sync params to Tournament Serializer

app/serializers/tournament_serializer.rb

@@ -2,13 +2,20 @@
 
 class TournamentSerializer < SimpleTournamentSerializer
   attributes :description, :playoff_teams_amount,
-             :instant_finalists_amount, :intermediate_round_participants_amount
+             :instant_finalists_amount, :intermediate_round_participants_amount,
+             :read_only_mode, :sync_target_url, :sync_last_push_error
+             # NEVER expose sync_auth_token anywhere - it should only ever be written to or checked against
+
   has_many :stages
 
   attribute :timer_end do
     object.timer_end&.iso8601
   end
 
+  attribute :sync_last_pushed_at do
+    object.sync_last_pushed_at&.iso8601
+  end
+
   attribute :owner_username do
     object.owner.username
   end