Redirect the other www spelling to SITE_ORIGIN, hold roles to the role help and fix the audit findings

SITE_ORIGIN alone decides whether the site is www or not: CanonicalHostSubscriber
sends the other spelling there with 301, cms:site:origin writes the setting, the
system screen shows it. The roles now match the role help (editor: drafts,
publisher: live content, admin: design, settings, users, system). The installer no
longer reopens on an unreachable database, the session cookie follows ADMIN_PATH,
percent-encoded credentials no longer break the container, consent only accepts
same-site decisions, JSON-LD is HTML-safe, own CSS stays in its block, plus the
editor, updater, download and public-output findings from the full review
(ADR 099, ADR 100).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

templates/admin/settings.html.twig

@@ -53,6 +53,7 @@
 </section>
 <section class="stack-section">
     <div class="section-head"><h2>Unternehmensdaten</h2><span class="muted">Grundlage für Organization und LocalBusiness</span></div>
+    {% if is_granted('ROLE_ADMIN') %}
     <form action="{{ path('admin_settings_save') }}" method="post" class="card card-body">
         <input type="hidden" name="_csrf_token" value="{{ csrf_token('settings') }}">
         <div class="fields">
@@ -273,6 +274,9 @@
 
         <button class="primary" type="submit">Einstellungen speichern</button>
     </form>
+    {% else %}
+    <p class="card card-body muted">Unternehmensdaten, Knopf „nach oben“, Spamschutz und Einwilligung ändert nur ein Administrator.</p>
+    {% endif %}
 </section>
 
 <section class="stack-section">