Allow section registration in info.xml

[tomneedham]

Description

Section classes can be registered in info.xml by specifying the class name like so:

<settings-sections>
     <admin>OCA\Files_antivirus\AdminSection</admin>
</settings-sections>

This allows apps to register their own sections, with translatable titles, and specify an icon to be used (although this must be in core at the moment).

Related Issue

#27327

How Has This Been Tested?

Moved the files_antivirus app to its own section for testing.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly. [Info provided in this PR]
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[tomneedham]

This will reintroduce the error message when unknown sections are referenced which I believe is the correct reaction, as we should encourage section registration to enable translation support

[DeepDiver1975]

@tomneedham is there an app which can be used for testing? THX