Enhance Supervisor Dashboard and Trainee Feedback Features

- Redesigned the supervisor overview page to include a header card with supervisor details and trainee statistics.
- Implemented a tabbed interface for viewing trainees and their recent attempts.
- Improved the trainee detail page with a profile card and a table for displaying attempt history.
- Added a new view for supervisors to provide feedback on case collections, including outstanding feedback items and previous conversations.
- Updated URL routing to support new feedback functionality.
- Enhanced backend logic to ensure proper sharing permissions for exam attempts and case collections.
- Added comprehensive tests for supervisor access to trainee data and feedback functionalities.

templates/base.html

@@ -314,6 +314,11 @@
                                     <a class="nav-link active" href="{% url 'people' %}">People</a>
                                 </li>
                             {% endif %}
+                            {% if request.user.supervisor %}
+                                <li id="supervisor-link" class="nav-item">
+                                    <a class="nav-link active" href="{% url 'generic:supervisor_overview' request.user.supervisor.pk %}">Supervisor</a>
+                                </li>
+                            {% endif %}
                             <li id="profile-link" class=" nav-item">
                                 <a class="nav-link active" href="{% url 'profile' %}">Profile</a>
                             </li>