Add ticket status setter and prevent draft text loss

- Set ticket state (Offen / In Bearbeitung / Warten auf Schließen /
  Geschlossen) from the ticket detail page via a live PUT to Zammad;
  pending-close gets a default pending time and the change is synced back
  so it isn't flagged as an external change
- Replace the disruptive meta-refresh with a JS auto-refresh that pauses
  while a text field has unsent content or focus
- Persist reply/new-ticket drafts to localStorage and restore them after
  a reload or accidental navigation

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

templates/ticket.html

@@ -20,6 +20,16 @@
     <div><dt>zuletzt geändert</dt><dd>{{ ticket.zammad_updated_at|dt }}</dd></div>
     <div><dt>geschlossen</dt><dd>{{ ticket.last_close_at|dt }}</dd></div>
   </dl>
+  <form method="post" action="{{ url_for('set_state', ticket_id=ticket.id) }}" class="state-form">
+    <label for="state_id">Status ändern:</label>
+    <select id="state_id" name="state_id">
+      {% for s in settable_states %}
+        <option value="{{ s.id }}" {{ 'selected' if s.id == ticket.state_id }}>{{ s.label }}</option>
+      {% endfor %}
+    </select>
+    <button class="btn-sm" type="submit">setzen</button>
+    <span class="hint-inline">wirkt live in Zammad</span>
+  </form>
 </section>
 
 <section class="panel">
@@ -75,7 +85,7 @@
   {% if ticket.state != 'closed' %}
   <form method="post" action="{{ url_for('reply_preview', ticket_id=ticket.id) }}"
         class="reply-form attach-form" enctype="multipart/form-data">
-    <textarea name="body" rows="4" required
+    <textarea name="body" rows="4" required data-draft
               placeholder="Antwort an den EPI-Support verfassen… (Screenshot mit Strg+V einfügen)"></textarea>
     {% include "_attach.html" %}
     <div class="form-actions">