The problem appears to have been resolved by the provider. Services should be back to normal operation again.

The provider has confirmed the issue and is working on a fix:
https://status.hetzner.com/incident/27caef14-784b-4aad-bd3c-e2c8e00f799d

One of our storage backends, used for providing large data storage for certain services that may scale up to many gigabytes of storage, is currently unavailable. Continuing to monitor.

Not fully available are:
- Some posts on szuru.libre.moe and kirei.libre.moe
- Data stored in seafile.libre.moe
- Attachments, project media, CI logs, LFS-storage and other non-Git-related data in lab.libre.moe
- Attachments, images and other media in chat.libre.moe