Add missing docblocks and return types.

src/Libs/Neuron.php

@@ -19,11 +19,23 @@
 namespace Libs;
 
 class Neuron {
+
+    /**
+     * __construct
+     *
+     * @param object|array $data
+     */
     public function __construct(array|object $data = []) {
         foreach($data as $key => $value)
             $this->{$key} = $value;
     }
 
+    /**
+     * __get
+     *
+     * @param string $index
+     * @return mixed
+     */
     public function __get(string $index) {
         return (isset($this->{$index}) &&
                 $this->{$index} != '') ? $this->{$index} : null;