Initial commit: Port Nimara CRM (Layers 0-4)

Full CRM rebuild with Next.js 15, TypeScript, Tailwind, Drizzle ORM,
PostgreSQL, Redis, BullMQ, MinIO, and Socket.io. Includes 461 source
files covering clients, berths, interests/pipeline, documents/EOI,
expenses/invoices, email, notifications, dashboard, admin, and
client portal. CI/CD via Gitea Actions with Docker builds.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/app/not-found.tsx

@@ -0,0 +1,19 @@
+import Link from 'next/link';
+
+export default function NotFound() {
+  return (
+    <div className="min-h-screen flex flex-col items-center justify-center gap-4 px-4 text-center">
+      <h1 className="text-4xl font-bold text-foreground">404</h1>
+      <p className="text-lg font-medium text-foreground">Page not found</p>
+      <p className="text-sm text-muted-foreground">
+        The page you are looking for does not exist or has been moved.
+      </p>
+      <Link
+        href="/dashboard"
+        className="mt-2 text-sm underline underline-offset-4 text-muted-foreground hover:text-foreground transition-colors"
+      >
+        Back to dashboard
+      </Link>
+    </div>
+  );
+}