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/tailwindcss/plugin.d.ts

@@ -0,0 +1,11 @@
+import type { Config, PluginCreator } from './types/config'
+type Plugin = {
+  withOptions<T>(
+    plugin: (options: T) => PluginCreator,
+    config?: (options: T) => Partial<Config>
+  ): { (options: T): { handler: PluginCreator; config?: Partial<Config> }; __isOptionsFunction: true }
+  (plugin: PluginCreator, config?: Partial<Config>): { handler: PluginCreator; config?: Partial<Config> }
+}
+
+declare const plugin: Plugin
+export = plugin