Add syncPropValues method to Propable trait; update StoreProductRequest and UpdateProductRequest to handle props validation

app/Domains/Prop/Support/PropRules.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace App\Domains\Prop\Support;
+
+class PropRules
+{
+    /**
+     * @return array<string, mixed>
+     */
+    public static function sync(): array
+    {
+        return [
+            'props' => ['sometimes', 'array'],
+            'props.*' => ['nullable'],
+        ];
+    }
+}