Admin runs a script to add a new OAuth 2.0 client to a MediaWiki instance. After the script runs, admin will provide client ID, secret, authorization URL, and token URL to client to configure the client application.

There could also be a self-service interface in the future, but that is out of scope for this epic.

Priority: Must Have

Acceptance Criteria:

Run the script:

1. Pass in redirect URI for the client to the script
2. Script generates client ID and secret
3. Script stores client ID and redirect URI in the MediaWiki database
4. Script returns client ID and secret