refactor: separate standalone and managed room configs

- veins → shunts rename
- add cfg/standalone/ and cfg/<room>/ structure
- remove old data/*.json (moved to cfg/<room>/data/)
- update build.py and ctrl scripts

artery/index.html

@@ -428,14 +428,7 @@
                 <div
                     class="vein{% if vein.status == 'live' or vein.status == 'building' %} active{% else %} disabled{% endif %}{% if loop.first %} selected{% endif %}"
                     data-tab="{{ vein.slug }}"
-                    {%
-                    if
-                    vein.status=""
-                    ="planned"
-                    %}data-disabled="true"
-                    {%
-                    endif
-                    %}
+                    {% if vein.status == "planned" %}data-disabled="true"{% endif %}
                 >
                     <h3>{{ vein.title }}</h3>
                 </div>