Add a separate page for rejected alerts

We don’t want to mix these up with alerts that actually went out.

app/main/views/broadcast.py

@@ -51,7 +51,6 @@ def broadcast_dashboard_previous(service_id):
         broadcasts=BroadcastMessages(service_id).with_status(
             'cancelled',
             'completed',
-            'rejected',
         ),
         page_title='Previous alerts',
         empty_message='You do not have any previous alerts',
@@ -59,6 +58,21 @@ def broadcast_dashboard_previous(service_id):
     )
 
 
+@main.route('/services/<uuid:service_id>/rejected-alerts')
+@user_has_permissions()
+@service_has_permission('broadcast')
+def broadcast_dashboard_rejected(service_id):
+    return render_template(
+        'views/broadcast/previous-broadcasts.html',
+        broadcasts=BroadcastMessages(service_id).with_status(
+            'rejected',
+        ),
+        page_title='Rejected alerts',
+        empty_message='You do not have any rejected alerts',
+        view_broadcast_endpoint='.view_rejected_broadcast',
+    )
+
+
 @main.route('/services/<uuid:service_id>/broadcast-dashboard.json')
 @user_has_permissions()
 @service_has_permission('broadcast')
@@ -345,6 +359,10 @@ def preview_broadcast_message(service_id, broadcast_message_id):
     '/services/<uuid:service_id>/previous-alerts/<uuid:broadcast_message_id>',
     endpoint='view_previous_broadcast',
 )
+@main.route(
+    '/services/<uuid:service_id>/rejected-alerts/<uuid:broadcast_message_id>',
+    endpoint='view_rejected_broadcast',
+)
 @user_has_permissions()
 @service_has_permission('broadcast')
 def view_broadcast(service_id, broadcast_message_id):
@@ -356,7 +374,7 @@ def view_broadcast(service_id, broadcast_message_id):
         abort(404)
 
     if (
-        broadcast_message.status in {'completed', 'cancelled', 'rejected'}
+        broadcast_message.status in {'completed', 'cancelled'}
         and request.endpoint != 'main.view_previous_broadcast'
     ):
         return redirect(url_for(
@@ -375,9 +393,20 @@ def view_broadcast(service_id, broadcast_message_id):
             broadcast_message_id=broadcast_message.id,
         ))
 
+    if (
+        broadcast_message.status in {'rejected'}
+        and request.endpoint != 'main.view_rejected_broadcast'
+    ):
+        return redirect(url_for(
+            '.view_rejected_broadcast',
+            service_id=current_service.id,
+            broadcast_message_id=broadcast_message.id,
+        ))
+
     back_link_endpoint = {
         'main.view_current_broadcast': '.broadcast_dashboard',
         'main.view_previous_broadcast': '.broadcast_dashboard_previous',
+        'main.view_rejected_broadcast': '.broadcast_dashboard_rejected',
     }[request.endpoint]
 
     return render_template(