feat: center loader in carto

src/app/structure-list/structure-list.component.scss

@@ -6,6 +6,19 @@
 .structureList-container {
   overflow-y: auto;
   scrollbar-gutter: stable;
+  display: flex;
+  flex-direction: column;
+  flex: 1;
+
+  .listCard {
+    display: flex;
+    flex-direction: column;
+    flex: 1;
+
+    .loader {
+      margin: auto;
+    }
+  }
 }
 
 .listCard > p {