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/has-flag/index.js

@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = (flag, argv = process.argv) => {
+	const prefix = flag.startsWith('-') ? '' : (flag.length === 1 ? '-' : '--');
+	const position = argv.indexOf(prefix + flag);
+	const terminatorPosition = argv.indexOf('--');
+	return position !== -1 && (terminatorPosition === -1 || position < terminatorPosition);
+};