Add doctrine and seperate out the renderer

app/Entity/Book.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace App\Entity;
+
+use Doctrine\ORM\Mapping as ORM;
+
+#[ORM\Entity]
+#[ORM\Table(name: 'book')]
+class Book
+{
+    #[ORM\Id, ORM\Column, ORM\GeneratedValue]
+    private int $id;
+}