Add og:url, Twitter Card meta, og:type event on detail page

- base.html.twig: add og:url (dynamic), twitter:card, twitter:title, twitter:description
- event_detail: og:type = event
- All public pages already have title + description blocks that propagate to OG

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

templates/base.html.twig

@@ -68,11 +68,15 @@
         <meta property="og:title" content="{% block og_title %}{{ block('title') }}{% endblock %}">
         <meta property="og:description" content="{% block og_description %}{{ block('description') }}{% endblock %}">
         <meta property="og:type" content="{% block og_type %}website{% endblock %}">
+        <meta property="og:url" content="{{ app.request.uri }}">
         <meta property="og:locale" content="fr_FR">
         <meta property="og:site_name" content="E-Ticket">
         {% block og_image %}
             <meta property="og:image" content="https://ticket.e-cosplay.fr/logo.png">
         {% endblock %}
+        <meta name="twitter:card" content="summary_large_image">
+        <meta name="twitter:title" content="{{ block('og_title') }}">
+        <meta name="twitter:description" content="{{ block('og_description') }}">
     {% endblock %}
     {% block stylesheets %}{% endblock %}
     {% block javascripts %}