- Convert class references from strings to static ::class constants built-in to PHP for improved code completion and static analysis.

- Replace Facade references using the global namespace with their FQCN for improved code completion and static analysis.
- delete database\factories\PageFactory.php and app\services\Registrar.php

app/Providers/DoiServiceProvider.php

@@ -33,7 +33,7 @@ class DoiServiceProvider extends ServiceProvider
     public function register()
     {
         //
-        $this->app->singleton('App\Interfaces\DoiInterface', function ($app) {
+        $this->app->singleton(\App\Interfaces\DoiInterface::class, function ($app) {
             return new DoiClient();
         });
     }