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/use-callback-ref/dist/es2019/mergeRef.js

@@ -0,0 +1,18 @@
+import { assignRef } from './assignRef';
+import { createCallbackRef } from './createRef';
+/**
+ * Merges two or more refs together providing a single interface to set their value
+ * @param {RefObject|Ref} refs
+ * @returns {MutableRefObject} - a new ref, which translates all changes to {refs}
+ *
+ * @see {@link useMergeRefs} to be used in ReactComponents
+ * @example
+ * const Component = React.forwardRef((props, ref) => {
+ *   const ownRef = useRef();
+ *   const domRef = mergeRefs([ref, ownRef]); // 👈 merge together
+ *   return <div ref={domRef}>...</div>
+ * }
+ */
+export function mergeRefs(refs) {
+    return createCallbackRef((newValue) => refs.forEach((ref) => assignRef(ref, newValue)));
+}