feat: redesign Exams List page to show submitted custom exams

- Added Custom Exams tab showing all exams from Generation page
- Displays title, module badges, duration, and status
- Added Create Exam button
- Kept Exam Sessions tab for institutional sessions
- Search filters across exams

Made-with: Cursor

node_modules/dom-helpers/esm/insertAfter.js

@@ -0,0 +1,19 @@
+/**
+ * Inserts a node after a given reference node.
+ * 
+ * @param node the node to insert
+ * @param refNode the reference node
+ */
+export default function insertAfter(node, refNode) {
+  if (node && refNode && refNode.parentNode) {
+    if (refNode.nextSibling) {
+      refNode.parentNode.insertBefore(node, refNode.nextSibling);
+    } else {
+      refNode.parentNode.appendChild(node);
+    }
+
+    return node;
+  }
+
+  return null;
+}