M0: Skelett + Auth-Grundgerüst (Keycloak-OIDC + API-Token)

- Symfony 7.4 LTS, PHP 8.4, FrankenPHP, SQLite (3-Layer src/UI|Logic|Data)
- Auth: manueller OidcClient (Authorization-Code) im UI-Layer, kein
  Security-Bundle/league; Session-Gate via SessionAuthSubscriber
- API-Guard via statischem X-Api-Token (ApiTokenSubscriber); ExceptionSubscriber
- UserEntity (Auto-Provision) + Init-Migration
- Docker (php:8.4-frankenphp) + compose (essen.ljh31.de, traefik-net external)
- SmokeTests (7) grün: Redirect-Fälle, API-Token, Auth-Render, Logout

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

templates/home/index.html.twig

@@ -0,0 +1,13 @@
+{% extends 'layout/base.html.twig' %}
+
+{% block title %}Start · svc-essensplanung{% endblock %}
+
+{% block body %}
+    <h1>{{ name }}</h1>
+    <div class="card">
+        <p>Willkommen zur Essensplanung! (M0-Skelett)</p>
+        <p><strong>E-Mail:</strong> {{ email }}</p>
+        <p><strong>Redirect-Pfad:</strong> <code>{{ redirect }}</code></p>
+        <p>M1: CRUD-Slice (Dish-Create/Update/Delete/List) folgt.</p>
+    </div>
+{% endblock %}