App crashes with no useful log messages when attempting upload of large number of photos

Steps to reproduce

1. Select a large amount of photos to upload.
2. Select "Done"
3. App shows upload options screen for several seconds (presumably while trying to generate thumbnails, since no thumbnails appear) and then crashes.

The limit where the app crashes seems to be somewhere between about 300 and 500 selected images/videos for upload. Due to issue #2406, it was too time consuming to try to narrow it down further.

Expected behaviour

App should not crash.

Actual behaviour

App crashes.

Logs

There is no log output in the log file relating to the crash, even with log level set to "maximum".
The last message in the log before the messages from restarting the app to get the logfile was from several minutes prior, which was the several minutes spent selecting a large group of pictures (see issue #2406).

2023-05-01 12:44:47 Network request body: None
2023-05-01 12:50:33 [INFO] Start session with level 2 Nextcloud Liquid for iOS 4.8.0.5 <C2><A9> 2023 in state 1 where (0 active, 1 inactive, 2 background).
2023-05-01 12:50:33 DATABASE FOUND in /private/var/mobile/Containers/Shared/AppGroup/...

Environment data

iOS version: iOS 16.4.1

Nextcloud iOS app version: 4.8.0.5

Server operating system: Debian 11 amd64

Web server: Apache

Database: MariaDB 10.5.18

PHP version: 7.4.33

Nextcloud version: 22.2.10

Start by reproducing the crash on iOS 16.4.1 with Nextcloud iOS 4.8.0.5 using roughly 300–500 selected photos or videos. Compare behavior around thumbnail generation and inspect why maximum-level logging produces no crash-related message. Done means large selections no longer crash and the failure provides useful log output if an error remains.