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/react-remove-scroll-bar/dist/es5/index.d.ts

@@ -0,0 +1,4 @@
+import { RemoveScrollBar } from './component';
+import { zeroRightClassName, fullWidthClassName, noScrollbarsClassName, removedBarSizeVariable } from './constants';
+import { getGapWidth } from './utils';
+export { RemoveScrollBar, zeroRightClassName, fullWidthClassName, noScrollbarsClassName, removedBarSizeVariable, getGapWidth, };