500 error after update to Drupal core 11.4.2

Problem/Motivation

After updating to Drupal core 11.4.2, pages can fail with a 500 error when the Visitors module is enabled.

The failure happens while Drupal is constructing the visitors.visibility service:

TypeError: Drupal\visitors\Service\VisibilityService::__construct():
Argument #4 ($path_matcher) must be of type Drupal\Core\Path\PathMatcher,
Drupal\path_alias\AliasPathMatcher given

Drupal core now decorates the path.matcher service with Drupal\path_alias\AliasPathMatcher. That class correctly implements Drupal\Core\Path\PathMatcherInterface, but it is not an instance of the concrete Drupal\Core\Path\PathMatcher class currently type-hinted by Visitors.

Steps to reproduce

1. Install Drupal core 11.4.2.
2. Enable the core Path Alias module.
3. Install and enable Visitors 8.x-2.32.
4. Load a page where visitors_page_attachments() runs.
5. The page returns a 500 error because visitors.visibility cannot be constructed.

Proposed resolution

Update Drupal\visitors\Service\VisibilityService to type-hint Drupal\Core\Path\PathMatcherInterface instead of the concrete Drupal\Core\Path\PathMatcher class.

The service already only depends on path matcher behavior exposed by the interface, so no service definition change is needed. The existing @path.matcher service argument remains correct.

Also update the related unit test mock and PHPDoc annotations to use PathMatcherInterface.

Remaining tasks

• Add/update test coverage so the constructor accepts a PathMatcherInterface implementation.
• Review and commit the patch.

User interface changes

None.

API changes

The constructor type hint for VisibilityService changes from PathMatcher to PathMatcherInterface. This is a compatible loosening of the accepted dependency type.

Data model changes

None.