Add EPI-Support monitoring & analytics platform

Internal Flask app that monitors the epi-helpdesk.zammad.com tickets via
the Zammad API, deployable as a systemd service behind Apache under
/episupport.

Features:
- Poller: session-login API sync, snapshot diff to detect agent changes
  (status, owner, priority, closures, new replies); email notifications
- Dashboard: ticket overview with sorting, "not closed" filter and
  highlighting of tickets with unconfirmed changes; per-item and bulk
  "mark as read"
- Analytics: KPIs, response/resolution times, monthly SVG trend chart,
  distributions (status/priority/group/agent), Excel export
- Conversation view: full per-ticket thread cached in the DB (avoids
  proxy timeouts), inline image attachments, safe HTML-to-text rendering
- Write actions: reply to tickets and create new tickets with a
  confirmation step and attachment upload (incl. clipboard paste);
  self-triggered actions are synced back so they aren't flagged as changes
- Local timezone display (Europe/Berlin) for all timestamps

Includes deploy tooling: setup.sh, systemd units and Apache config.

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

templates/ticket.html

@@ -25,6 +25,9 @@
 <section class="panel">
   <div class="panel-head">
     <h2>Konversation{% if conversation %} ({{ conversation|length }}){% endif %}</h2>
+    <form method="post" action="{{ url_for('refresh_conversation', ticket_id=ticket.id) }}">
+      <button class="btn-sm" type="submit">↻ Aktualisieren</button>
+    </form>
   </div>
   {% if conv_error %}
     <p class="muted">Konversation konnte nicht geladen werden: {{ conv_error }}</p>
@@ -42,7 +45,25 @@
           {% if a.subject %}<div class="msg-subj">{{ a.subject }}</div>{% endif %}
           <div class="msg-body">{{ a.body }}</div>
           {% if a.attachments %}
-            <div class="msg-att">📎 {{ a.attachments|join(', ') }}</div>
+            {% set imgs = a.attachments|selectattr('is_image')|list %}
+            {% set files = a.attachments|rejectattr('is_image')|list %}
+            {% if imgs %}
+              <div class="msg-imgs">
+                {% for att in imgs %}
+                  <a href="{{ url_for('attachment', ticket_id=ticket.id, article_id=a.id, att_id=att.id) }}" target="_blank" rel="noopener">
+                    <img class="msg-img" loading="lazy" alt="{{ att.filename }}"
+                         src="{{ url_for('attachment', ticket_id=ticket.id, article_id=a.id, att_id=att.id) }}">
+                  </a>
+                {% endfor %}
+              </div>
+            {% endif %}
+            {% if files %}
+              <div class="msg-att">
+                {% for att in files %}
+                  📎 {% if att.id %}<a href="{{ url_for('attachment', ticket_id=ticket.id, article_id=a.id, att_id=att.id) }}" target="_blank" rel="noopener">{{ att.filename }}</a>{% else %}{{ att.filename }}{% endif %}
+                {% endfor %}
+              </div>
+            {% endif %}
           {% endif %}
         </article>
       {% endfor %}
@@ -52,9 +73,11 @@
   {% endif %}
 
   {% if ticket.state != 'closed' %}
-  <form method="post" action="{{ url_for('reply_preview', ticket_id=ticket.id) }}" class="reply-form">
+  <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
-              placeholder="Antwort an den EPI-Support verfassen…"></textarea>
+              placeholder="Antwort an den EPI-Support verfassen… (Screenshot mit Strg+V einfügen)"></textarea>
+    {% include "_attach.html" %}
     <div class="form-actions">
       <span class="hint-inline">Geht nach Bestätigung live an EPI.</span>
       <button class="btn-sm" type="submit">Antworten →</button>
@@ -84,3 +107,4 @@
   {% endif %}
 </section>
 {% endblock %}
+{% block scripts %}<script src="{{ url_for('static', filename='upload.js') }}"></script>{% endblock %}