update return type & type hinting

Author: emrancu

bootstrap/System/Api.php

@@ -11,19 +11,19 @@
 class Api implements ApiInterface
 {
     /**
-     * @var string
+     * @var string|null
      */
-    public static string $prefix;
+    public static ?string $prefix;
 
     /**
      * @var string
      */
-    private static string $middleware;
+    private static ?string $middleware = null;
 
     /**
-     * @var ApiHandler
+     * @var ApiHandler|null
      */
-    private static ApiHandler $apiHandler;
+    private static ?ApiHandler $apiHandler = null;
 
     /**
      * setting up api prefix and middleware as array with  $config

bootstrap/System/DependencyInjectionContainer.php

@@ -60,10 +60,10 @@ public function call($callable, array $parameters = [])
     /**
      * initiate the class and return the instance.
      * @param string $id
-     * @return mixed|string
+     * @return object
      * @throws \ReflectionException
      */
-    public function get(string $id)
+    public function get(string $id): object
     {
         if (!isset($this->instances[$id])) {
             $this->instances[$id] = $this->make($id);