Initialize pre-stages with respective half duration

Having the halftime duration being zero may confuse people.

Author: g3force

internal/app/engine/engine.go

@@ -450,6 +450,7 @@ func (e *Engine) createInitialState() (s *state.State) {
 	}
 	s.NextCommand = state.NewCommand(state.Command_KICKOFF, *s.FirstKickoffTeam)
 	s.PlacementPos = geom.NewVector2(0.0, 0.0)
+	s.StageTimeLeft = durationpb.New(e.gameConfig.Normal.HalfTimeDuration)
 	return
 }
 

internal/app/statemachine/statemachine.go

@@ -44,12 +44,16 @@ func loadStageTimes(gameConfig config.Game) (s map[state.Referee_Stage]time.Dura
 	for stage := range state.Referee_Stage_name {
 		s[state.Referee_Stage(stage)] = 0
 	}
+	s[state.Referee_NORMAL_FIRST_HALF_PRE] = gameConfig.Normal.HalfDuration
 	s[state.Referee_NORMAL_FIRST_HALF] = gameConfig.Normal.HalfDuration
 	s[state.Referee_NORMAL_HALF_TIME] = gameConfig.Normal.HalfTimeDuration
+	s[state.Referee_NORMAL_SECOND_HALF_PRE] = gameConfig.Normal.HalfDuration
 	s[state.Referee_NORMAL_SECOND_HALF] = gameConfig.Normal.HalfDuration
 	s[state.Referee_EXTRA_TIME_BREAK] = gameConfig.Normal.BreakAfter
+	s[state.Referee_EXTRA_FIRST_HALF_PRE] = gameConfig.Overtime.HalfDuration
 	s[state.Referee_EXTRA_FIRST_HALF] = gameConfig.Overtime.HalfDuration
 	s[state.Referee_EXTRA_HALF_TIME] = gameConfig.Overtime.HalfTimeDuration
+	s[state.Referee_EXTRA_SECOND_HALF_PRE] = gameConfig.Overtime.HalfDuration
 	s[state.Referee_EXTRA_SECOND_HALF] = gameConfig.Overtime.HalfDuration
 	s[state.Referee_PENALTY_SHOOTOUT_BREAK] = gameConfig.Overtime.BreakAfter
 	return