Draft: Add oauth to Web IDE

• gitlab-web-ide Spike MR for OAuth
  • Part 1 - refactor: Add AuthType to support OAuth (!247 - merged)
  • Part 2 - refactor: Set up OAuthClient and oauthCallback ... (!250 - merged)
  • Pre-Part 3 - feat: Add utils-crypto package (!252 - merged)
  • Part 3 - feat: Implementing OAuthClient (!251 - merged)
  • In Parallel:
    • Logging - chore: Add minLogLevel to config (!257 - closed)
    • Secret Storage Provider - feat: Add secretStorageProvider to workbench op... (!263 - merged)
    • Broadcasting - feat: Add broadcaster to OAuth (!264 - merged)
    • Extra - chore: Add logger package (!248 - merged)
• gitlab Spike MR

Description

This is the draft MR of adding oauth to the Web IDE. It will be split up into smaller MR's.

What all is going on here?

• Adds Authentication Type field to the example app which corresponds to auth.type in the main config.
• Adds oauth-client package to manage initializing and refreshing the oauth token.
• Adds secretStorageProvider to the VSCode workbench options to expose the auth_headers to GitLab VSCode extensions. This can be accessed using context.secrets.get('auth_headers').
• In the gitlab-api-client, the authHeaders option is replaced with an authProvider. The authProvider is called every time we need headers. If we're using oauth, this means we can choose to refresh if needed.
• Adds a decorator for broadcasting oauth changes to other tabs.

How to test?

Follow the instructions in this documentation:

https://gitlab.com/gitlab-org/gitlab-web-ide/-/blob/7ff05919a11822ddb52b4aac204c963608f77cf8/docs/dev/development_environment_setup.md#setup-example-app-with-oauth-to-local-gdk

Screenshots

Description	Screenshot
Demo	20231001_web_ide_example_demo
New Authentication Type field in example app config
OAuth handshake screen in example app