CRISTAL-381: Make the github backend supported

[pjeanjean]

Jira URL

https://jira.xwiki.org/browse/CRISTAL-381

Changes

Description

• Working authentication
• Content display
• Content edition
• Content deletion
• Updated navigation tree to use public API
• Updated history to use public API

Clarifications

Login operations for the GitHub API have to be done in the backend. As such, a new backend has been implemented in ./github-authentication. It requires to set a Client ID for a GitHub app that has repo:read and repo:write permissions for the repository the user wants to use. This can be set in ./github-authentication/src/config.ts.

While working on this issue, I noticed that the transformImage was not working properly (i.e., mutation listeners were in fact not triggered on document change). I don't know since when this happens, but I added a simpler transformImagesInElements() function that should have, as an added benefit, less performance impact for this purpose.

Screenshots & Video

Executed Tests

Each new and changed feature was tested manually, and the current test suite was run manually.

Expected merging strategy

• Prefers squash: Yes
• Backport on branches:
  • N/A

[manuelleduc]

• edit is displayed even when not logged in
• missing header on history query
• for now, we'll keep using the same json based storage, we'll switch for all backends at once (makes it easier to support internal links, new pages creation and attachments)
• document all the setup in the wiki

[manuelleduc]

1. introduce authentication-github-ui
2. load it from github.ts in lib
3. move GitHubLoginMenu.vue in authentication-github-ui and define an extension UI component for it, with a sidebar.actions UIXP
4. update GitHubLoginMenu.vue to have an empty activator (see AttachmentPreview.vue for inspiration)
5. on GitHubAuthenticationManager.start change the vmodel of GitHubLoginMenu.vue to make the modal visible