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/date-fns/locale/hr.d.mts

@@ -0,0 +1,11 @@
+import type { Locale } from "./types.js";
+/**
+ * @category Locales
+ * @summary Croatian locale.
+ * @language Croatian
+ * @iso-639-2 hrv
+ * @author Matija Marohnić [@silvenon](https://github.com/silvenon)
+ * @author Manico [@manico](https://github.com/manico)
+ * @author Ivan Jeržabek [@jerzabek](https://github.com/jerzabek)
+ */
+export declare const hr: Locale;