add serializer to activityController

src/Bundle/ChillActivityBundle/Resources/views/Activity/newPerson.html.twig

@@ -12,9 +12,12 @@
     <script src="{{ asset('build/async_upload.js') }}" type="text/javascript"></script>
     <script type="text/javascript">
         chill.displayAlertWhenLeavingUnsubmittedForm('form[name="{{ form.vars.form.vars.name }}"]', '{{ "You are going to leave a page with unsubmitted data. Are you sure you want to leave ?"|trans }}');
+        window.activity = {{ activity_json|e('json') }};
     </script>
+    {{ encore_entry_script_tags('vue_activity') }}
 {% endblock %}
 
 {% block css %}
     <link rel="stylesheet" href="{{ asset('build/async_upload.css') }}"/>
+    {{ encore_entry_link_tags('vue_activity') }}
 {% endblock %}