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/semver/ranges/ltr.js

@@ -0,0 +1,6 @@
+'use strict'
+
+const outside = require('./outside')
+// Determine if version is less than all the versions possible in the range
+const ltr = (version, range, options) => outside(version, range, '<', options)
+module.exports = ltr