Refactor Microsot Auth into a testable class with expanded error handling

[barakiva]

Summary

Web/microsoft-auth.php previously handled only the success path of
Microsoft's OAuth 2.0 authorization code flow. Per the Microsoft identity
platform docs, the callback endpoint receives two distinct response shapes:

• Success: ?code=...&state=...
• Error: ?error=...&error_description=...

Error responses were silently ignored — the page would redirect to
Web with no error header, causing a confusing failure
downstream with no diagnostic information.

Changes

• Extract callback logic into MicrosoftOAuthCallback (lib/Application/Authentication/)
  with a MicrosoftOAuthCallbackResult value object representing the two
  outcome cases. This makes the code more testable.
• Handle error responses from Azure: redirect to home and log the error/description
• unit tests covering success, URL encoding, error with/without description,
  error-takes-precedence-over-code, and missing params
• Add workflow_dispatch trigger to CI workflows to allow manual runs on forks so contributors can make sure PRs will pass CI before submitting to upstream

Not addressed in this PR

• state parameter verification — the Microsoft docs recommend verifying the
  returned state matches the value sent in the authorization request as a
  CSRF mitigation. This would require storing the state server-side before the
  redirect, which is a larger change.

Any feedback on testing & class design would be appreicated.

[Copilot]

Pull request overview

Refactors the Microsoft OAuth2 callback endpoint into a dedicated handler/value-object pair to support both success and error callback shapes, improve diagnostics, and make the logic unit-testable.

Changes:

• Extract callback parsing/redirect resolution into MicrosoftOAuthCallback + MicrosoftOAuthCallbackResult.
• Log and redirect on Azure error responses rather than silently failing.
• Add unit tests for success/error/missing params and URL encoding; enable workflow_dispatch for CI workflows.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 10 comments.

Show a summary per file

File	Description
Web/microsoft-auth.php	Uses the new callback handler and adds error logging before redirecting.
lib/Application/Authentication/MicrosoftOAuthCallback.php	Introduces the callback handler and result value object for success/error outcomes.
tests/Application/Authentication/MicrosoftOAuthCallbackTest.php	Adds unit tests covering success, encoding, and error/missing-params behavior.
.github/workflows/phpunit.yml	Adds manual workflow trigger (workflow_dispatch).
.github/workflows/lint-and-analyse-php.yml	Adds manual workflow trigger (workflow_dispatch).
.github/workflows/integration-tests.yml	Adds manual workflow trigger (workflow_dispatch).
.github/workflows/docs.yml	Adds manual workflow trigger (workflow_dispatch).

[barakiva]

Applied all code reivew suggestions and unit tests all pass.