Replaced demo with local instance url in OpenApiDocs

[lachiebol]

Description

Removed mentions of demo.matomo.cloud.

Updated path resolver to post an event that allows other plugins to modify the artifact path used, will do a cloud PR to hook into that event

Issue No

Steps to Replicate the Issue

Checklist

• [✔] Tested locally or on demo2/demo3?
• [✔] New test case added/updated?
• [NA] Are all newly added texts included via translation?
• [NA] Are text sanitized properly? (Eg use of v-text v/s v-html for vue)
• [NA] Version bumped?
• [NA] Documentation updated?

[lachiebol]

@AltamashShaikh I'll also do a cloud PR that hooks into OpenApiDocs.getArtifactBasePath and changes the path

[AltamashShaikh]

Looks good, few concerns by AI to check

 High-risk issues (blocking)

  - The new event dispatch breaks the unit test path that used to work without a container. testReturnsPluginLocalPathsWhenCloudIsDisabled() now constructs a real
    PathResolver in tests/Unit/Specs/PathResolverTest.php:26, and getSpecDirectory() immediately calls Piwik::postEvent() through Specs/PathResolver.php:82. Running
    vendor/bin/phpunit --bootstrap tests/PHPUnit/proxy/includes.php plugins/OpenApiDocs/tests/Unit/Specs/PathResolverTest.php from the Matomo root errors with
    ContainerDoesNotExistException. That is a concrete regression introduced by this refactor.


  Low-risk / polish

  - Several docblocks in Annotations/AnnotationGenerator.php:857 still describe the behavior as querying demo.matomo.cloud, which is now inaccurate.
  - The PathResolver test suite mocks dispatchArtifactBasePathEvent() for most cases but not the default-path test, which is why the regression slipped through. The
    tests should consistently isolate external event dispatch.

[lachiebol]

High-risk issues (blocking)

• The new event dispatch breaks the unit test path that used to work without a container. testReturnsPluginLocalPathsWhenCloudIsDisabled() now constructs a real
  PathResolver in tests/Unit/Specs/PathResolverTest.php:26, and getSpecDirectory() immediately calls Piwik::postEvent() through Specs/PathResolver.php:82. Running
  vendor/bin/phpunit --bootstrap tests/PHPUnit/proxy/includes.php plugins/OpenApiDocs/tests/Unit/Specs/PathResolverTest.php from the Matomo root errors with
  ContainerDoesNotExistException. That is a concrete regression introduced by this refactor.

@AltamashShaikh Is this an issue? We just require the full bootstrap.php rather than includes.php. Seems like it's more of an integration test now that we rely on Piwik::postEvent()

› matomo_5x-dev  5.x-dev !2 ?8  ddev matomo:console tests:run plugins/OpenApiDocs                                                                                                                                                                        ✔
  Executing command: cd /var/www/html/tests/PHPUnit &&  /var/www/html/vendor/bin/phpunit   ../../plugins/OpenApiDocs

  If these tests time out consistently, it can be helpful to temporarily set testdox=true in the phpunit.xml.dist in order to see which test is causing the issue.
  PHPUnit 8.5.52 by Sebastian Bergmann and contributors.

  Runtime:       PHP 8.2.30
  Configuration: /var/www/html/tests/PHPUnit/phpunit.xml.dist

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