feat : init Central project — Symfony 8 + Nuxt 4 + Docker starter

Same architecture as Lesstime: API Platform 4, JWT auth, @malio/layer-ui,
PostgreSQL 16, Docker Compose (ports 8083/3003/5436), dark mode theme.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/Kernel.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App;
+
+use Symfony\Bundle\FrameworkBundle\Kernel\MicroKernelTrait;
+use Symfony\Component\HttpKernel\Kernel as BaseKernel;
+
+class Kernel extends BaseKernel
+{
+    use MicroKernelTrait;
+}