round30: alle drei Scanner als Hintergrund-Job, Dienst-Duplikate strukturell verhindert (Migration+Constraint+Geraete-Sperre), zweiter Erkennungsversuch bei leerem Ersttreffer

apps/frontend/src/hooks/useScanActivity.ts

@@ -22,16 +22,18 @@ export function useScanActivity(): ScanActivity {
 
     async function poll() {
       try {
-        const [devicesRes, apisRes] = await Promise.all([
+        const [devicesRes, apisRes, fritzboxRes] = await Promise.all([
           fetch("/api/scan/devices/all/status"),
           fetch("/api/scan/apis/status"),
+          fetch("/api/scan/fritzbox/status"),
         ]);
         if (cancelled) return;
 
         const devicesStatus = devicesRes.ok ? await devicesRes.json() : null;
         const apisStatus = apisRes.ok ? await apisRes.json() : null;
+        const fritzboxStatus = fritzboxRes.ok ? await fritzboxRes.json() : null;
 
-        const running = !!devicesStatus?.running || !!apisStatus?.running;
+        const running = !!devicesStatus?.running || !!apisStatus?.running || !!fritzboxStatus?.running;
 
         const lastResult = devicesStatus?.lastResult;
         const pendingCount = lastResult

apps/frontend/src/routes/admin/ScannerPage.tsx

@@ -18,22 +18,6 @@ interface DeviceChange {
   suggested: string;
 }
 
-interface FritzBoxScanResult {
-  found: number;
-  uniqueDevices: number;
-  staleDevices: Device[];
-  deviceChanges: DeviceChange[];
-}
-
-async function scanFritzBox(): Promise<FritzBoxScanResult> {
-  const res = await fetch("/api/scan/fritzbox", { method: "POST" });
-  const body = await res.json();
-  if (!res.ok) {
-    throw new Error(body.error ?? `FritzBox-Scan fehlgeschlagen (HTTP ${res.status})`);
-  }
-  return body;
-}
-
 async function patchDevice(id: string, patch: Record<string, unknown>) {
   const res = await fetch(`/api/devices/${id}`, {
     method: "PATCH",
@@ -441,18 +425,56 @@ export function ScannerPage() {
     null
   );
 
-  const fritzboxMutation = useMutation({
-    mutationFn: scanFritzBox,
-    onSuccess: (result) => {
-      setFritzboxSummary({ found: result.found, uniqueDevices: result.uniqueDevices });
-      setFritzboxError(null);
-      setStaleDevices(result.staleDevices);
-      setDeviceChanges(result.deviceChanges);
-      queryClient.invalidateQueries({ queryKey: ["devices"] });
-      queryClient.invalidateQueries({ queryKey: ["logs"] });
-    },
-    onError: (error: Error) => setFritzboxError(error.message),
-  });
+  const [fritzboxRunning, setFritzboxRunning] = useState(false);
+  const lastFritzboxHandledAt = useRef<string | null>(null);
+
+  useEffect(() => {
+    let cancelled = false;
+
+    async function poll() {
+      try {
+        const res = await fetch("/api/scan/fritzbox/status");
+        if (!res.ok || cancelled) return;
+        const s = await res.json();
+
+        setFritzboxRunning(s.running);
+
+        if (!s.running && s.lastResult && s.startedAt !== lastFritzboxHandledAt.current) {
+          lastFritzboxHandledAt.current = s.startedAt;
+          setFritzboxSummary({ found: s.lastResult.found, uniqueDevices: s.lastResult.uniqueDevices });
+          setFritzboxError(null);
+          setStaleDevices(s.lastResult.staleDevices);
+          setDeviceChanges(s.lastResult.deviceChanges);
+          queryClient.invalidateQueries({ queryKey: ["devices"] });
+          queryClient.invalidateQueries({ queryKey: ["logs"] });
+        } else if (!s.running && s.lastError && s.startedAt !== lastFritzboxHandledAt.current) {
+          lastFritzboxHandledAt.current = s.startedAt;
+          setFritzboxError(s.lastError);
+        }
+      } catch {
+        // Netzwerk-Hänger beim Poll soll nicht die Seite stören.
+      }
+    }
+
+    poll();
+    const interval = setInterval(poll, 1500);
+    return () => {
+      cancelled = true;
+      clearInterval(interval);
+    };
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, []);
+
+  async function startFritzboxScan() {
+    setFritzboxError(null);
+    const res = await fetch("/api/scan/fritzbox", { method: "POST" });
+    if (!res.ok) {
+      const body = await res.json().catch(() => ({}));
+      setFritzboxError(body.error ?? `Fehlgeschlagen (HTTP ${res.status})`);
+      return;
+    }
+    setFritzboxRunning(true);
+  }
 
   // Geräteübergreifender Sammel-Scan: läuft als Hintergrund-Job im Backend
   // (siehe apps/backend/src/scanJobs.ts), nicht mehr als Schleife aus
@@ -548,10 +570,10 @@ export function ScannerPage() {
           <Button
             variant="primary"
             className="mt-4"
-            onClick={() => fritzboxMutation.mutate()}
-            disabled={fritzboxMutation.isPending}
+            onClick={startFritzboxScan}
+            disabled={fritzboxRunning}
           >
-            {fritzboxMutation.isPending ? "Scanne …" : "FritzBox jetzt scannen"}
+            {fritzboxRunning ? "Scanne …" : "FritzBox jetzt scannen"}
           </Button>
           {fritzboxSummary ? (
             <p className="mt-2 text-sm text-emerald-600 dark:text-emerald-400">