Split AKModel views into different files & introduce modular status page

• Move AKModel views into several subfiles to improve overview and resolve problems with circular imports
• Introduce new modular status page handling (widgets and views)
• Port main status page to new structure
• Move AK messages status page visualization to AKSubmission (therefore, they automatically do not show up when there is no possibility to create them)
• Introduce status widget for virtual rooms
• Fix timezone issue for rendering of AK messages on status page
• Adapt status page URL in several views and tests

This lays the foundation for #105

AKModel/templates/admin/AKModel/status/status.html

@@ -15,13 +15,13 @@
                     <div class="card-header">
                         {% if widget.actions %}
                             <div class="float-end">
-                                <a class="" data-bs-toggle="dropdown" aria-expanded="false">
-                                    {% fa6_icon "ellipsis-vertical" %}
+                                <a style="cursor: pointer;" data-bs-toggle="dropdown" aria-expanded="false">
+                                    &nbsp;{% fa6_icon "ellipsis-vertical" %}&nbsp;
                                 </a>
                                 <ul class="dropdown-menu dropdown-menu-end">
                                     {% for action in widget.actions %}
-                                    <li>
-                                        <a class="dropdown-item" href="{{ action.url }}">{{ action.text }}</a>
+                                    <li class="dropdown-item">
+                                        <a href="{{ action.url }}">{{ action.text }}</a>
                                     </li>
                                     {% endfor %}
                                 </ul>