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/index.html

@@ -43,6 +43,16 @@
                             </div>
                         {% endif %}
 
+                        {% if request.user.supervisor %}
+                            <div class="card mb-3 border border-info bg-dark bg-opacity-25">
+                                <div class="card-body">
+                                    <h5 class="card-title text-info"><i class="bi bi-person-workspace me-2"></i>Supervisor Dashboard</h5>
+                                    <p class="card-text text-muted mb-3">Welcome, {{ request.user.supervisor.name }}. You can track, review, and leave feedback on your trainees' attempts here.</p>
+                                    <a class="btn btn-outline-info" href="{% url 'generic:supervisor_overview' request.user.supervisor.pk %}">Go to Dashboard</a>
+                                </div>
+                            </div>
+                        {% endif %}
+
                         <div class="card mb-3">
                             <div class="card-body">
                                 <h5 class="card-title">Exams / Courses</h5>