Fix 8 critical/high resilience issues across camera, preview, logger, settings, and admin

src/screens/AdminScreen.tsx

@@ -65,6 +65,7 @@ export default function AdminScreen({ currentSettings, onSave, onClose }: AdminS
   const [countdown, setCountdown] = useState<string>(String(currentSettings.countdownDuration));
   const [printerIp, setPrinterIp] = useState<string>(currentSettings.printerIp);
   const [password, setPassword] = useState<string>(currentSettings.adminPassword);
+  const [isTogglingKiosk, setIsTogglingKiosk] = useState<boolean>(false);
   const [logs, setLogs] = useState<string | null>(null);
   const scrollViewRef = useRef<ScrollView>(null);
   
@@ -98,7 +99,9 @@ export default function AdminScreen({ currentSettings, onSave, onClose }: AdminS
     return () => clearInterval(interval);
   }, []);
 
-  const handleKioskToggle = (enable: boolean) => {
+  const handleKioskToggle = async (enable: boolean) => {
+    if (isTogglingKiosk) return;
+    setIsTogglingKiosk(true);
     try {
       if (enable) {
         const success = KioskMode.startKiosk();
@@ -124,6 +127,8 @@ export default function AdminScreen({ currentSettings, onSave, onClose }: AdminS
       }
     } catch (e: any) {
       Alert.alert('Nativer Fehler', e.message || 'Fehler im Kiosk-Modul');
+    } finally {
+      setIsTogglingKiosk(false);
     }
   };
 
@@ -298,6 +303,7 @@ export default function AdminScreen({ currentSettings, onSave, onClose }: AdminS
               placeholder="Standard: 1234"
               placeholderTextColor={THEME.colors.textMuted}
               secureTextEntry
+              maxLength={20}
               value={password}
               onChangeText={setPassword}
               keyboardType="number-pad"