fix(widgets): replace old page before showing pagination skeleton

tests/widget-system/zibll-modern-widgets-contract.test.cjs

@@ -47,8 +47,8 @@ test('widget REST client keeps the skeleton across the load-more cycle', () => {
   assert.match(frontend, /loader\.classList\.add\('is-loading'\)/);
   assert.doesNotMatch(frontend, /loader\.style\.display/);
 
-  // The skeleton is anchored to the end of the list on every request, exactly
-  // like the reference post_ajax beforeSend hook.
+  // The loader follows any retained rows and precedes the pagination controls.
+  // Replacement clears old rows before loading; runtime tests cover that cycle.
   assert.match(frontend, /function anchorLoader\(container\) \{/);
   assert.match(frontend, /if \(!loader\) return null;/);
   assert.match(frontend, /pag\.parentNode\.insertBefore\(loader, pag\)/);
@@ -57,8 +57,6 @@ test('widget REST client keeps the skeleton across the load-more cycle', () => {
   // flush under the last card.
   assert.match(frontend, /var anchor = loaderOf\(container\) \|\| container\.querySelector\(':scope > \.ajax-pag'\);/);
 
-  // A replace must preserve the loader node (the reference success only hides it).
-  assert.match(frontend, /if \(child !== loader && !child\.classList\.contains\('ajax-pag'\)\) child\.remove\(\);/);
   assert.match(frontend, /return fetch\(itemsUrl\(/);
 });