Feature OAuth 2.0 support

[StanBarrows]

No description provided.

[Copilot]

Pull Request Overview

This PR introduces OAuth 2.0 support for Bexio by implementing a new OAuth service, token store, and associated controller along with updates to the connector, routes, configuration and documentation.

• Added tests to cover OAuth token storage, refreshing, userinfo fetching and verification.
• Implemented new classes such as BexioOAuthService, BexioOAuthTokenStore, BexioOAuthExceptionHandler, and BexioOAuthViewBuilder.
• Updated the BexioConnector to leverage OAuth2 flows and refresh logic, and adjusted configuration/routes/README accordingly.

Reviewed Changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/Support/BexioTokenStoreTest.php	Added tests for caching, retrieving, overwriting, and forgetting the authenticator.
tests/Services/BexioOAuthServiceTest.php	Ensured proper behavior for exchanging codes, token refreshes, and userinfo fetching.
tests/Requests/OpenID/FetchUserinfoRequestTest.php	Validated proper mapping of the userinfo response to the DTO.
tests/Controllers/BexioOAuthControllerTest.php	Added comprehensive tests for the OAuth redirect and callback flows.
src/Support/*	New support classes for OAuth view building, token storage, and exception handling.
src/Services/BexioOAuthService.php	Implements code exchange, token refresh, userinfo fetching, and verification logic.
src/Http/Controllers/BexioOAuthController.php	New controller handling the OAuth redirect and callback logic.
src/BexioConnector.php	Updated connector to support OAuth2, including token refresh within the request boot.
routes/bexio.php, config/bexio.php, README.md	Added/updated OAuth-specific routes, settings, and documentation.

Comments suppressed due to low confidence (2)

src/BexioConnector.php:50

• Consider adding a comment explaining why you are specifically checking for instances of GetRefreshTokenRequest to prevent recursive token refresh calls.

if ($pendingRequest->getRequest() instanceof GetRefreshTokenRequest) {

README.md:19

• [nitpick] The markdown table formatting was updated; please ensure it remains consistent with the project's style guidelines.

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