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/why-is-node-running/example.js

@@ -0,0 +1,15 @@
+var log = require('./')
+var net = require('net')
+
+function createServer () {
+  var server = net.createServer()
+  setInterval(function () {}, 1000)
+  server.listen(0)
+}
+
+createServer()
+createServer()
+
+setTimeout(function () {
+  log()
+}, 100)