feat: Einbinden des Footers in Landing-, Admin- und Login-Ansicht

templates/login.html

@@ -30,6 +30,11 @@
             <a href="{{ url_for('index', instance_id=instance_id) }}" class="btn btn-secondary w-100 mt-2">Zurück zur
                 Kasse</a>
         </form>
+        <div class="mt-4 text-center text-muted pb-4">
+            <small>Made with ♥️, marmalade and zero knowledge in <a href="https://kiel-sailing-city.de/"
+                    target="_blank">Kiel Strawberry City.</a><br>
+                Version: {{ version }}, Instanz: {{ instance_id[:8] }}...</small>
+        </div>
     </div>
     <script>
         if ('serviceWorker' in navigator) {