fix 5m period, fix websocket not responding on no data

internal/metrics/period/handler.go

@@ -71,9 +71,6 @@ func (p *Poller[T, AggregateT]) getRespData(r *http.Request) (any, error) {
 		return nil, errors.New("invalid period")
 	}
 	rangeData := p.Get(periodFilter)
-	if len(rangeData) == 0 {
-		return nil, nil
-	}
 	if p.aggregator != nil {
 		total, aggregated := p.aggregator(rangeData, query)
 		return map[string]any{

internal/metrics/period/period.go

@@ -38,6 +38,7 @@ func (p *Period[T]) Add(info *T) {
 	p.mu.Lock()
 	defer p.mu.Unlock()
 	now := time.Now()
+	p.FiveMinutes.Add(now, info)
 	p.FifteenMinutes.Add(now, info)
 	p.OneHour.Add(now, info)
 	p.OneDay.Add(now, info)