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/clear.js

@@ -0,0 +1,16 @@
+/**
+ * Removes all child nodes from a given node.
+ * 
+ * @param node the node to clear
+ */
+export default function clear(node) {
+  if (node) {
+    while (node.firstChild) {
+      node.removeChild(node.firstChild);
+    }
+
+    return node;
+  }
+
+  return null;
+}