Fix Camera permissions and enable front camera fallback on Android

src/screens/CameraScreen.tsx

@@ -8,6 +8,7 @@ import {
   Modal,
   TextInput,
   TouchableWithoutFeedback,
+  PermissionsAndroid,
 } from 'react-native';
 import { CameraView, useCameraPermissions } from 'expo-camera';
 import * as FileSystem from 'expo-file-system';
@@ -131,7 +132,24 @@ export default function CameraScreen({
     if (permission && !permission.granted && permission.canAskAgain) {
       requestPermission();
     }
-  }, []);
+    
+    // Specifically for ausbc native library which needs these at runtime
+    if (Platform.OS === 'android') {
+      const requestAndroidPerms = async () => {
+        try {
+          const granted = await PermissionsAndroid.requestMultiple([
+            PermissionsAndroid.PERMISSIONS.CAMERA,
+            PermissionsAndroid.PERMISSIONS.WRITE_EXTERNAL_STORAGE,
+            PermissionsAndroid.PERMISSIONS.READ_EXTERNAL_STORAGE,
+          ]);
+          logger.log('Android Permissions:', JSON.stringify(granted));
+        } catch (err) {
+          console.warn('Failed to request Android permissions', err);
+        }
+      };
+      requestAndroidPerms();
+    }
+  }, [permission]);
 
   // 2. Check if a USB camera is connected.
   useEffect(() => {
@@ -400,29 +418,27 @@ export default function CameraScreen({
     }
   };
 
-  // On iOS we need the expo-camera permission, on Android we bypass it since we use USB
+  // Show permission block if built-in camera has no permission AND USB is not connected
-  if (Platform.OS !== 'android') {
+  if (!permission) {
-    if (!permission) {
+    return (
-      return (
+      <View style={styles.container}>
-        <View style={styles.container}>
+        <Text style={styles.infoText}>Berechtigungen werden geladen...</Text>
-          <Text style={styles.infoText}>Berechtigungen werden geladen...</Text>
+      </View>
-        </View>
+    );
-      );
+  }
-    }
 
-    if (!permission.granted && !isUsbConnected) {
+  if (!permission.granted && !isUsbConnected) {
-      return (
+    return (
-        <View style={styles.container}>
+      <View style={styles.container}>
-          <Text style={styles.infoText}>Wir benötigen deine Erlaubnis, um die Kamera anzuzeigen</Text>
+        <Text style={styles.infoText}>Wir benötigen deine Erlaubnis, um die Tablet-Kamera anzuzeigen</Text>
-          <TouchableOpacity style={styles.btn} onPress={requestPermission}>
+        <TouchableOpacity style={styles.btn} onPress={requestPermission}>
-            <Text style={styles.btnText}>Erlaubnis erteilen</Text>
+          <Text style={styles.btnText}>Erlaubnis erteilen</Text>
-          </TouchableOpacity>
+        </TouchableOpacity>
-          <TouchableOpacity style={[styles.btn, styles.cancelBtn]} onPress={handleLocalCancel}>
+        <TouchableOpacity style={[styles.btn, styles.cancelBtn]} onPress={handleLocalCancel}>
-            <Text style={styles.btnText}>Zurück</Text>
+          <Text style={styles.btnText}>Zurück</Text>
-          </TouchableOpacity>
+        </TouchableOpacity>
-        </View>
+      </View>
-      );
+    );
-    }
   }
 
   const renderContent = () => {
@@ -628,7 +644,7 @@ export default function CameraScreen({
       {/* Camera Preview Background */}
       <View style={styles.previewContainer}>
         <View style={styles.cameraWrapper}>
-          {Platform.OS === 'android' ? (
+          {Platform.OS === 'android' && isUsbConnected ? (
             <UsbCameraView 
               ref={usbCameraRef} 
               style={[styles.cameraPreview, { position: 'absolute', opacity: 1, zIndex: 10 }]}