feat(comfyuimini): add "Manage Photos" sidebar link to the Gallery

ComfyUIMini's built-in gallery is view-only. Inject a "Manage Photos"
link into its sidebar (via the shared head.ejs partial at build time, so
no fork) that points to the Model Manager's delete-capable Gallery. The
URL is built client-side from the browser host; the port is baked from
the MODEL_MANAGER_PORT build arg (default 8189).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

comfyuimini/sparky-sidebar.html

@@ -0,0 +1,20 @@
+<!-- SparkyUI: inject a "Manage Photos" link into the ComfyUIMini sidebar that
+     points to the Model Manager's delete-capable Gallery. The URL is built
+     client-side from the browser host so it works on any LAN address. The
+     __MM_PORT__ token is replaced with MODEL_MANAGER_PORT at build time. -->
+<script>
+(function () {
+  document.addEventListener('DOMContentLoaded', function () {
+    var list = document.getElementById('sidebar-list');
+    if (!list || document.getElementById('sparky-gallery-link')) return;
+    var a = document.createElement('a');
+    a.id = 'sparky-gallery-link';
+    a.className = 'sidebar-list-item';
+    a.href = location.protocol + '//' + location.hostname + ':__MM_PORT__/?view=gallery';
+    a.innerHTML =
+      '<span class="icon gallery"></span>' +
+      '<span class="sidebar-list-item-text">Manage Photos</span>';
+    list.appendChild(a);
+  });
+})();
+</script>