Stand: SMTP-Test, Admin-Mail-Tab, Notifiable-Fix, Lazy-Quill

- Fix: Notifiable-Trait zum User-Model hinzugefuegt (behebt notify()-500er)
- Installer: SMTP-Verbindungstest mit EsmtpTransport + Ueberspringen-Link
- Admin: Neuer E-Mail-Tab mit SMTP-Konfiguration + Verbindungstest
- Admin: Lazy Quill-Initialisierung (nur sichtbare Locale wird geladen)
- Uebersetzungen: 17 neue Mail-Keys in allen 6 Sprachen

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vendor/ezyang/htmlpurifier/library/HTMLPurifier/ConfigSchema/schema/HTML.AllowedAttributes.txt

@@ -0,0 +1,19 @@
+HTML.AllowedAttributes
+TYPE: lookup/null
+VERSION: 1.3.0
+DEFAULT: NULL
+--DESCRIPTION--
+
+<p>
+    If HTML Purifier's attribute set is unsatisfactory, overload it!
+    The syntax is "tag.attr" or "*.attr" for the global attributes
+    (style, id, class, dir, lang, xml:lang).
+</p>
+<p>
+    <strong>Warning:</strong> If another directive conflicts with the
+    elements here, <em>that</em> directive will win and override. For
+    example, %HTML.EnableAttrID will take precedence over *.id in this
+    directive.  You must set that directive to true before you can use
+    IDs at all.
+</p>
+--# vim: et sw=4 sts=4