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/lodash/_castSlice.js

@@ -0,0 +1,18 @@
+var baseSlice = require('./_baseSlice');
+
+/**
+ * Casts `array` to a slice if it's needed.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {number} start The start position.
+ * @param {number} [end=array.length] The end position.
+ * @returns {Array} Returns the cast slice.
+ */
+function castSlice(array, start, end) {
+  var length = array.length;
+  end = end === undefined ? length : end;
+  return (!start && end >= length) ? array : baseSlice(array, start, end);
+}
+
+module.exports = castSlice;