feat: implement QuestionBank CRUD with pagination and template query

- Add pagination support to findAll (page, limit query params)
- Add findByTemplateId method to service
- Add GET /by-template/:templateId endpoint to controller
- Service already includes CRUD for QuestionBank and QuestionBankItem

web/src/utils/cn.ts

@@ -0,0 +1,6 @@
+import { type ClassValue, clsx } from 'clsx';
+import { twMerge } from 'tailwind-merge';
+
+export function cn(...inputs: ClassValue[]) {
+    return twMerge(clsx(inputs));
+}

web/src/utils/toast.ts

@@ -0,0 +1,31 @@
+
+type ToastType = 'success' | 'error' | 'warning' | 'info';
+
+interface ToastHandler {
+  showToast: (type: ToastType, message: string, title?: string) => void;
+}
+
+let handler: ToastHandler | null = null;
+
+export const registerToastHandler = (h: ToastHandler) => {
+  handler = h;
+};
+
+export const toast = {
+  success: (message: string, title?: string) => {
+    if (handler) handler.showToast('success', message, title);
+    else console.log(`✅ ${message}`);
+  },
+  error: (message: string, title?: string) => {
+    if (handler) handler.showToast('error', message, title);
+    else console.log(`❌ ${message}`);
+  },
+  info: (message: string, title?: string) => {
+    if (handler) handler.showToast('info', message, title);
+    else console.log(`ℹ️ ${message}`);
+  },
+  warning: (message: string, title?: string) => {
+    if (handler) handler.showToast('warning', message, title);
+    else console.log(`⚠️ ${message}`);
+  }
+};