fix: eliminate PHPUnit warnings and deprecations in test suite

Set defaultTestSuite="CoreCore" to prevent 222 duplicate file warnings,
and replace deprecated isType() with isArray()/isString() in notification
listener tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

modules/notifications/tests/Module/Notifications/Listeners/UserActivatedNotificationListenerTest.php

@@ -51,7 +51,7 @@ final class UserActivatedNotificationListenerTest extends TestCase
                 'admin/users/edit/user-uuid',
                 ['user_id' => 10, 'uuid' => 'user-uuid'],
                 5,
-                $this->isType('array')
+                $this->isArray()
             );
 
         $this->listener->handle('user.activated', [

modules/notifications/tests/Module/Notifications/Listeners/UserAssignmentChangedNotificationListenerTest.php

@@ -44,9 +44,9 @@ final class UserAssignmentChangedNotificationListenerTest extends TestCase
                 null,
                 'user.assignment_changed',
                 $this->stringContains('Alice'),
-                $this->isType('string'),
+                $this->isString(),
                 'admin/users/edit/user-uuid',
-                $this->isType('array')
+                $this->isArray()
             )
             ->willReturn(99);
 
@@ -56,11 +56,11 @@ final class UserAssignmentChangedNotificationListenerTest extends TestCase
                 1,
                 'user.assignment_changed',
                 $this->stringContains('Alice'),
-                $this->isType('string'),
+                $this->isString(),
                 'admin/users/edit/user-uuid',
-                $this->isType('array'),
+                $this->isArray(),
                 7,
-                $this->isType('array')
+                $this->isArray()
             )
             ->willReturn(1);
 

modules/notifications/tests/Module/Notifications/Listeners/UserDeactivatedNotificationListenerTest.php

@@ -51,7 +51,7 @@ final class UserDeactivatedNotificationListenerTest extends TestCase
                 'admin/users/edit/user-uuid',
                 ['user_id' => 10, 'uuid' => 'user-uuid'],
                 5,
-                $this->isType('array')
+                $this->isArray()
             );
 
         $this->listener->handle('user.deactivated', [