add Dependencies and Routes classes

src/Dependencies.php

@@ -0,0 +1,29 @@
+<?php
+declare(strict_types=1);
+
+namespace NoteCat;
+
+use DI\Container;
+use Psr\Container\ContainerInterface;
+
+class Dependencies
+{
+    public static function createContainer(): Container
+    {
+        $container = new Container();
+
+        // Controllers
+        $container->set(HelloWorldController::class, function (ContainerInterface $c) {
+            return new HelloWorldController(
+                $c->get(HelloWorld::class)
+            );
+        });
+
+        // Services
+        $container->set(HelloWorld::class, function () {
+            return new HelloWorld();
+        });
+
+        return $container;
+    }
+}