Optimize file cleanup logic to retain image files and support multiple application type selection

This will fix the issue of deleting cache when deleting by mistake causing the background to close directly.

manager/app/src/main/java/shirkneko/zako/sukisu/ui/screen/Install.kt

@@ -275,7 +275,7 @@ private class HorizonKernelWorker(private val context: Context) : Thread() {
     }
 
     private fun cleanup() {
-        runCommand(false, "rm -rf ${context.filesDir.absolutePath}/*")
+        runCommand(false, "find ${context.filesDir.absolutePath} -type f ! -name '*.jpg' ! -name '*.png' -delete")
     }
 
     private fun copy() {
@@ -445,6 +445,7 @@ private fun SelectInstallMethod(onSelected: (InstallMethod) -> Unit = {}) {
             is InstallMethod.SelectFile, is InstallMethod.HorizonKernel -> {
                 selectImageLauncher.launch(Intent(Intent.ACTION_GET_CONTENT).apply {
                     type = "application/*"
+                    putExtra(Intent.EXTRA_MIME_TYPES, arrayOf("application/octet-stream", "application/zip"))
                 })
             }
             is InstallMethod.DirectInstall -> {