feat: complete tOS project with HR, LEAN, Dashboard and Integrations modules

Full enterprise web operating system including:
- Next.js 14 frontend with App Router, i18n (DE/EN), shadcn/ui
- NestJS 10 backend with Prisma, JWT auth, Swagger docs
- Keycloak 24 SSO with role-based access control
- HR module (employees, time tracking, absences, org chart)
- LEAN module (3S planning, morning meeting SQCDM, skill matrix)
- Integrations module (PlentyONE, Zulip, Todoist, FreeScout, Nextcloud, ecoDMS, GembaDocs)
- Dashboard with customizable drag & drop widget grid
- Docker Compose infrastructure (PostgreSQL 16, Redis 7, Keycloak 24)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/src/app/[locale]/error.tsx

@@ -0,0 +1,55 @@
+'use client';
+
+import { useEffect } from 'react';
+import { useTranslations } from 'next-intl';
+import { motion } from 'framer-motion';
+import { RefreshCw, Home } from 'lucide-react';
+import Link from 'next/link';
+
+import { Button } from '@/components/ui/button';
+
+interface ErrorPageProps {
+  error: Error & { digest?: string };
+  reset: () => void;
+}
+
+/**
+ * Error boundary page
+ * Displays when an unhandled error occurs
+ */
+export default function ErrorPage({ error, reset }: ErrorPageProps) {
+  const t = useTranslations('errors');
+
+  useEffect(() => {
+    // Log the error to an error reporting service
+    console.error('Application error:', error);
+  }, [error]);
+
+  return (
+    <div className="flex min-h-screen flex-col items-center justify-center bg-background p-4">
+      <motion.div
+        initial={{ opacity: 0, y: 20 }}
+        animate={{ opacity: 1, y: 0 }}
+        transition={{ duration: 0.4 }}
+        className="text-center"
+      >
+        <h1 className="text-6xl font-bold text-destructive">!</h1>
+        <h2 className="mt-4 text-2xl font-semibold">{t('serverError')}</h2>
+        <p className="mt-2 text-muted-foreground">{t('serverErrorDescription')}</p>
+
+        <div className="mt-8 flex gap-4 justify-center">
+          <Button onClick={reset} variant="outline">
+            <RefreshCw className="mr-2 h-4 w-4" />
+            {t('tryAgain')}
+          </Button>
+          <Button asChild>
+            <Link href="/dashboard">
+              <Home className="mr-2 h-4 w-4" />
+              {t('goHome')}
+            </Link>
+          </Button>
+        </div>
+      </motion.div>
+    </div>
+  );
+}