feat: add four new student modules (rotation, skill-video, exam-prep, academic) with backend APIs and frontend pages; add exam-prep question history with DB persistence

web/postcss.config.mjs

@@ -0,0 +1,7 @@
+const config = {
+  plugins: {
+    "@tailwindcss/postcss": {},
+  },
+};
+
+export default config;