Export from version 5.0 fails on importing in version 7.0 even success message available

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Steps to reproduce

1. Export users on a Nextcloud 28.0 instance (User Migration 5.0)
2. Transfer file to new Nextcloud 30.0 instance (User Migration 7.0) and start import
3. Find in the UI a success message BUT in the Nextcloud notification an error message that import failed

Expected behaviour

Import should be possible when exporting.

Actual behaviour

When exporting an account without any data (just calender entries) and importing all works fine.
For an account with approx. 200 MB of data it failes for the above described scenario with the above described error / success messages.

Server configuration

Web server: Apache

Database: MySQL/Maria

PHP version: 8.3

Nextcloud version: export on: 28.0.8 | import on: 30.0.1

Detailled error message in Nextcloud logs
{"reqId":"DLolciUhMsrT9OmUoABN","level":3,"time":"2025-03-01T13:55:01+00:00","remoteAddr":"","user":"--","app":"user_migration","method":"","url":"--","message":"Invalid or uninitialized Zip object","userAgent":"--","version":"30.0.1.2","exception":{"Exception":"ValueError","Message":"Invalid or uninitialized Zip object","Code":0,"Trace":[{"file":"/var/www/nextcloud/lib/private/Archive/ZIP.php","line":147,"function":"getFromName","class":"ZipArchive","type":"->"},{"file":"/var/www/nextcloud/apps/user_migration/lib/ImportSource.php","line":56,"function":"getFile","class":"OC\\Archive\\ZIP","type":"->"},{"file":"/var/www/nextcloud/apps/user_migration/lib/ImportSource.php","line":148,"function":"getFileContents","class":"OCA\\UserMigration\\ImportSource","type":"->"},{"file":"/var/www/nextcloud/apps/user_migration/lib/ImportSource.php","line":160,"function":"getMigratorVersions","class":"OCA\\UserMigration\\ImportSource","type":"->"},{"file":"/var/www/nextcloud/lib/public/UserMigration/TMigratorBasicVersionHandling.php","line":36,"function":"getMigratorVersion","class":"OCA\\UserMigration\\ImportSource","type":"->"},{"file":"/var/www/nextcloud/apps/user_migration/lib/Service/UserMigrationService.php","line":234,"function":"canImport","class":"OCA\\UserMigration\\Service\\UserMigrationService","type":"->"},{"file":"/var/www/nextcloud/apps/user_migration/lib/BackgroundJob/UserImportJob.php","line":100,"function":"import","class":"OCA\\UserMigration\\Service\\UserMigrationService","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/Job.php","line":61,"function":"run","class":"OCA\\UserMigration\\BackgroundJob\\UserImportJob","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/QueuedJob.php","line":43,"function":"start","class":"OCP\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/QueuedJob.php","line":29,"function":"start","class":"OCP\\BackgroundJob\\QueuedJob","type":"->"},{"file":"/var/www/nextcloud/cron.php","line":162,"function":"execute","class":"OCP\\BackgroundJob\\QueuedJob","type":"->"}],"File":"/var/www/nextcloud/lib/private/Archive/ZIP.php","Line":147,"message":"Invalid or uninitialized Zip object","exception":[],"CustomMessage":"Invalid or uninitialized Zip object"},"id":"67c316736b4b8"}

Start with apps/user_migration/lib/ImportSource.php, especially the getFile and getFileContents path, then inspect lib/private/Archive/ZIP.php at the reported getFromName call. Reproduce a migration from Nextcloud 28.0.8 to 30.0.1 using an account with about 200 MB of data and compare the UI success message with the notification error. Done means the import completes without the invalid Zip object error and reports a consistent result.