feat: add notification center and reliable client presence

server/internal/httpapi/notifications_internal_test.go

@@ -3,6 +3,8 @@ package httpapi
 import (
 	"testing"
 	"time"
+
+	"rmm-openwrt/server/internal/model"
 )
 
 func TestNotificationRetryDelay(t *testing.T) {
@@ -16,3 +18,15 @@ func TestNotificationRetryDelay(t *testing.T) {
 		t.Fatalf("retry cap: got %s want 30m", got)
 	}
 }
+
+func TestNotificationQuietHoursAcrossMidnight(t *testing.T) {
+	settings := model.NotificationSettings{
+		Timezone: "UTC", QuietHoursEnabled: true, QuietHoursStart: "22:00", QuietHoursEnd: "08:00",
+	}
+	if !notificationQuietNow(settings, time.Date(2026, 7, 30, 23, 0, 0, 0, time.UTC)) {
+		t.Fatal("23:00 must be quiet")
+	}
+	if notificationQuietNow(settings, time.Date(2026, 7, 30, 12, 0, 0, 0, time.UTC)) {
+		t.Fatal("12:00 must not be quiet")
+	}
+}