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/it.d.ts

@@ -0,0 +1,11 @@
+import type { Locale } from "./types.js";
+/**
+ * @category Locales
+ * @summary Italian locale.
+ * @language Italian
+ * @iso-639-2 ita
+ * @author Alberto Restifo [@albertorestifo](https://github.com/albertorestifo)
+ * @author Giovanni Polimeni [@giofilo](https://github.com/giofilo)
+ * @author Vincenzo Carrese [@vin-car](https://github.com/vin-car)
+ */
+export declare const it: Locale;