You can use nextcloud with applications. One day I was playing with PDF files without a text layer. I have everything set up to automatically recognize and apply a text layer to PDF files.
Nextcloud has many features, you can look in more detail. File synchronization, working with mail, instant messengers and much more.

This section will be useful:
Flow
Flow configuration
Files access control
Denied access
Examples
Denying access to folders
Prevent uploading of specific files
Common misconfigurations
Available rules
Automated tagging of files
Assigning restricted and invisible tags
Example
Available rules
Executing actions
Retention of files
Example
Common misconfigurations