ui: replace custom loading spinners with IconSpinner component across multiple files

apps/web/src/pages/templates/[id].tsx

@@ -6,6 +6,7 @@ import {
   CardHeader,
   CardTitle,
   ConfirmDialog,
+  IconSpinner,
   Input,
   Label,
   StickySaveBar,
@@ -117,22 +118,7 @@ export default function TemplateEditorPage() {
     return (
       <DashboardLayout>
         <div className="flex items-center justify-center min-h-[400px]">
-          <div className="text-center">
-            <svg
-              className="h-8 w-8 animate-spin mx-auto text-neutral-900"
-              xmlns="http://www.w3.org/2000/svg"
-              fill="none"
-              viewBox="0 0 24 24"
-            >
-              <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" />
-              <path
-                className="opacity-75"
-                fill="currentColor"
-                d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"
-              />
-            </svg>
-            <p className="mt-2 text-sm text-neutral-500">Loading template...</p>
-          </div>
+          <IconSpinner />
         </div>
       </DashboardLayout>
     );