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/embla-carousel/components/NodeRects.d.ts

@@ -0,0 +1,12 @@
+export type NodeRectType = {
+    top: number;
+    right: number;
+    bottom: number;
+    left: number;
+    width: number;
+    height: number;
+};
+export type NodeRectsType = {
+    measure: (node: HTMLElement) => NodeRectType;
+};
+export declare function NodeRects(): NodeRectsType;