Refactor the namespace to com.sukisu.ultra, add IKsuInterface and LatestVersionInfo data classes, and remove obsolete classes and methods.

manager/app/src/main/java/com/sukisu/ultra/utils/AssetsUtil.kt

@@ -0,0 +1,26 @@
+package com.sukisu.ultra.utils
+
+import android.content.Context
+import java.io.File
+import java.io.FileOutputStream
+import java.io.IOException
+
+object AssetsUtil {
+    @Throws(IOException::class)
+    fun exportFiles(context: Context, src: String, out: String) {
+        val fileNames = context.assets.list(src)
+        if (fileNames?.isNotEmpty() == true) {
+            val file = File(out)
+            file.mkdirs()
+            fileNames.forEach { fileName ->
+                exportFiles(context, "$src/$fileName", "$out/$fileName")
+            }
+        } else {
+            context.assets.open(src).use { inputStream ->
+                FileOutputStream(File(out)).use { outputStream ->
+                    inputStream.copyTo(outputStream)
+                }
+            }
+        }
+    }
+}