feat(altcha): add altcha validation layer to login

templates/altcha.html.twig

@@ -0,0 +1,18 @@
+{% block altcha_widget %}
+    <style>
+        .altcha label {
+            margin-bottom: 0;
+        }
+    </style>
+    <altcha-widget
+        challengejson={{challengeJson}}
+        name={{form.vars.full_name}}
+        strings="{{translations}}"
+        hidelogo
+        hidefooter
+        workers= {{ workers }}
+        delay={{ delay }}
+        {{ debug ? 'debug' : ''}}
+        {{ mockError ? 'mockerror' : ''}}
+    ></altcha-widget>
+{% endblock %}