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/intervalToDuration.d.ts

@@ -0,0 +1,26 @@
+import type { Duration, Interval } from "./types.js";
+/**
+ * @name intervalToDuration
+ * @category Common Helpers
+ * @summary Convert interval to duration
+ *
+ * @description
+ * Convert a interval object to a duration object.
+ *
+ * @typeParam DateType - The `Date` type, the function operates on. Gets inferred from passed arguments. Allows to use extensions like [`UTCDate`](https://github.com/date-fns/utc).
+ *
+ * @param interval - The interval to convert to duration
+ *
+ * @returns The duration object
+ *
+ * @example
+ * // Get the duration between January 15, 1929 and April 4, 1968.
+ * intervalToDuration({
+ *   start: new Date(1929, 0, 15, 12, 0, 0),
+ *   end: new Date(1968, 3, 4, 19, 5, 0)
+ * })
+ * // => { years: 39, months: 2, days: 20, hours: 7, minutes: 5, seconds: 0 }
+ */
+export declare function intervalToDuration<DateType extends Date>(
+  interval: Interval<DateType>,
+): Duration;