onions: add onion service management

app/portal/templates/onion.html.j2

@@ -0,0 +1,16 @@
+{% extends "base.html.j2" %}
+{% from 'bootstrap5/form.html' import render_form %}
+{% from "tables.html.j2" import proxies_table %}
+
+{% block content %}
+    <h1 class="h2 mt-3">Onion Services</h1>
+    <h2 class="h3">
+        {{ onion.group.group_name }}: {{ onion.onion_name }}.onion
+        <a href="https://{{ onion.onion_name }}.onion/" class="btn btn-secondary btn-sm" target="_bypass"
+           rel="noopener noreferer">⎋</a>
+    </h2>
+
+    <div style="border: 1px solid #666;" class="p-3">
+        {{ render_form(form) }}
+    </div>
+{% endblock %}