Implemented settings, new scan, enhanced UI/UX

lib/feature/scan/presentation/scanner.dart

@@ -0,0 +1,80 @@
+import 'package:flutter/material.dart';
+import 'package:mobile_scanner/mobile_scanner.dart';
+
+/// StatefulWidget für den Barcode-Scanner mit grünem Border-Feedback
+class BarcodeScannerWidget extends StatefulWidget {
+  final Function(String) onBarcodeDetected;
+
+  const BarcodeScannerWidget({
+    Key? key,
+    required this.onBarcodeDetected,
+  }) : super(key: key);
+
+  @override
+  State<BarcodeScannerWidget> createState() => _BarcodeScannerWidgetState();
+}
+
+class _BarcodeScannerWidgetState extends State<BarcodeScannerWidget> {
+  bool _isDetected = false;
+  DateTime? _lastScannedTime;
+  final Duration _scanTimeout = const Duration(milliseconds: 2000); // 2 Sekunden Cooldown
+
+  void _handleBarcodeDetected(String barcode) {
+    final now = DateTime.now();
+
+    // Prüfe ob genug Zeit seit dem letzten erfolgreichen Scan vergangen ist
+    if (_lastScannedTime != null &&
+        now.difference(_lastScannedTime!).inMilliseconds < _scanTimeout.inMilliseconds) {
+      // Timeout nicht abgelaufen - ignoriere diesen Scan
+      debugPrint('Scan ignoriert - Cooldown aktiv');
+      return;
+    }
+
+    // Update letzte Scan-Zeit
+    _lastScannedTime = now;
+
+    // Rand grün färben
+    setState(() {
+      _isDetected = true;
+    });
+
+    // Nach 500ms wieder zurücksetzen
+    Future.delayed(const Duration(milliseconds: 500), () {
+      if (mounted) {
+        setState(() {
+          _isDetected = false;
+        });
+      }
+    });
+
+    // Callback aufrufen
+    widget.onBarcodeDetected(barcode);
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final screenHeight = MediaQuery.of(context).size.height;
+    final scannerHeight = screenHeight / 4;
+
+    return Container(
+      height: scannerHeight,
+      decoration: BoxDecoration(
+        border: Border.all(
+          color: _isDetected ? Colors.green : Colors.grey,
+          width: _isDetected ? 4 : 2,
+        ),
+      ),
+      child: MobileScanner(
+        onDetect: (capture) {
+          final List<Barcode> barcodes = capture.barcodes;
+
+          for (final barcode in barcodes) {
+            if (barcode.rawValue != null) {
+              _handleBarcodeDetected(barcode.rawValue!);
+            }
+          }
+        },
+      ),
+    );
+  }
+}