test(factories): add missing model factories for app test suite

Enable `HasFactory` on `Environment`, `Project`, `ScheduledTask`, and
`StandaloneDocker`, and add dedicated factories for related models to
stabilize feature/unit tests.

Also bump `visus/cuid2` to `^6.0` and refresh `composer.lock` with the
resulting dependency updates.

tests/Unit/ContainerHealthStatusTest.php

@@ -1,7 +1,6 @@
 <?php
 
 use App\Models\Application;
-use Mockery;
 
 /**
  * Unit tests to verify that containers without health checks are not