Group Level Wiki: BE Add new group settings to toggle wiki

Problem to solve

Group wikis need to be managed in the group settings, just like project wikis:

1. Enable/disable wiki.
2. Set wiki visibility.

Intended users

Further details

Proposal

This issue implements the necessary BE changes (adding new fields/models, exposing them through an API).

We can refactor the existing ProjectFeature functionality to support a GroupFeature. There was a previous attempt to do this in gitlab-foss!15060 (closed).

A breakdown of MRs:

• Database migration !31712 (closed)
• Model and validation
• Extract common logic from ProjectFeature !31700 (merged)
• Extract common logic from Project
• Policy class
• Controller action/helpers
• Frontend view, JS & CSS

Permissions and Security

Group wiki settings should only be available to:

• Group owners
• Group maintainers?
• Parent group owners/maintainers?

The visibility levels need to be restricted if the group or a parent group is private/internal.

Documentation

Availability & Testing

Links / references