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/d3-time-format/locale/ca-ES.json

@@ -0,0 +1,10 @@
+{
+  "dateTime": "%A, %e de %B de %Y, %X",
+  "date": "%d/%m/%Y",
+  "time": "%H:%M:%S",
+  "periods": ["AM", "PM"],
+  "days": ["diumenge", "dilluns", "dimarts", "dimecres", "dijous", "divendres", "dissabte"],
+  "shortDays": ["dg.", "dl.", "dt.", "dc.", "dj.", "dv.", "ds."],
+  "months": ["gener", "febrer", "març", "abril", "maig", "juny", "juliol", "agost", "setembre", "octubre", "novembre", "desembre"],
+  "shortMonths": ["gen.", "febr.", "març", "abr.", "maig", "juny", "jul.", "ag.", "set.", "oct.", "nov.", "des."]
+}