Update Next.js configuration and improve Sentry integration

- Added `serverExternalPackages` to the Next.js configuration to exclude Node-only packages from the webpack bundle, enhancing compatibility with React's RSC/client boundary.
- Refactored Sentry initialization and exception capturing to be asynchronous, ensuring proper handling of the Sentry DSN and preventing potential issues during Next.js builds.
- Updated the `Toaster` component import in the layout to improve UI consistency.

apps/webui/src/lib/sentry.ts

@@ -1,17 +1,23 @@
-import * as Sentry from '@sentry/node';
-import { env } from './env';
-
 let initialized = false;
 
-export function initWebuiSentry(): void {
-  if (initialized || !env.SENTRY_DSN) {
+export async function initWebuiSentry(): Promise<void> {
+  if (initialized) {
     return;
   }
+  const dsn = process.env.SENTRY_DSN?.trim();
+  if (!dsn) {
+    return;
+  }
+
+  // Import only when a DSN is configured. Loading `@sentry/node` at module
+  // scope patches Node builtins and can break Next.js page-data collection
+  // (`createContext is not a function`) during `next build`.
+  const Sentry = await import('@sentry/node');
   Sentry.init({
-    dsn: env.SENTRY_DSN,
-    environment: env.NODE_ENV,
+    dsn,
+    environment: process.env.NODE_ENV ?? 'production',
     release: 'nexumi-webui@0.1.0',
-    tracesSampleRate: env.NODE_ENV === 'production' ? 0.1 : 1.0,
+    tracesSampleRate: process.env.NODE_ENV === 'production' ? 0.1 : 1.0,
     initialScope: {
       tags: { service: 'webui' }
     }
@@ -19,10 +25,15 @@ export function initWebuiSentry(): void {
   initialized = true;
 }
 
-export function captureWebuiException(error: unknown, context?: Record<string, unknown>): void {
-  if (!env.SENTRY_DSN) {
+export async function captureWebuiException(
+  error: unknown,
+  context?: Record<string, unknown>
+): Promise<void> {
+  const dsn = process.env.SENTRY_DSN?.trim();
+  if (!dsn) {
     return;
   }
+  const Sentry = await import('@sentry/node');
   Sentry.withScope((scope) => {
     if (context) {
       scope.setExtras(context);