Add in-app qr code scanner

app/src/other/java/io/nekohasekai/sfa/vendor/Vendor.kt

@@ -1,6 +1,8 @@
 package io.nekohasekai.sfa.vendor
 
 import android.app.Activity
+import androidx.camera.core.ImageAnalysis
+import java.lang.Exception
 
 object Vendor : VendorInterface {
 
@@ -11,4 +13,10 @@ object Vendor : VendorInterface {
     override fun checkUpdate(activity: Activity, byUser: Boolean) {
     }
 
+    override fun createQRCodeAnalyzer(
+        onSuccess: (String) -> Unit,
+        onFailure: (Exception) -> Unit
+    ): ImageAnalysis.Analyzer? {
+        return null
+    }
 }