Traffic analytics: per-minute history, busiest visitors, charts, spike and daily-amount alerts

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

alerts.go

@@ -127,6 +127,7 @@ func (s *Server) problemsLocked(now time.Time) map[string]problem {
 			}
 		}
 	}
+	s.trafficProblemsLocked(now, edgeDown, add)
 	for _, x := range s.st.MailEgress {
 		if !x.Enabled || edgeDown[x.EdgeID] || siteDown[x.SiteID] {
 			continue