Initial commit: EGBE chatbot template

Stripped from vercel/chatbot (Apache 2.0):
- Dropped @vercel/* packages and AI Gateway
- Removed artifacts feature (code/text/sheet/image side panel)
- Switched AI provider to @ai-sdk/openai-compatible -> EGBE LiteLLM
- Replaced Vercel Blob upload with data URLs
- Dropped Redis resumable streams and rate limiter (in-memory now)
- Added Dockerfile (Next.js standalone) + entrypoint that runs migrations
- Wired DATABASE_URL, EGBE_AI_API_URL/KEY, NEXT_PUBLIC_BASE_URL for app-deploy.sh

proxy.ts

@@ -0,0 +1,51 @@
+import { type NextRequest, NextResponse } from "next/server";
+import { getToken } from "next-auth/jwt";
+import { guestRegex, isDevelopmentEnvironment } from "./lib/constants";
+
+export async function proxy(request: NextRequest) {
+  const { pathname } = request.nextUrl;
+
+  if (pathname.startsWith("/ping")) {
+    return new Response("pong", { status: 200 });
+  }
+
+  if (pathname.startsWith("/api/auth")) {
+    return NextResponse.next();
+  }
+
+  const token = await getToken({
+    req: request,
+    secret: process.env.AUTH_SECRET,
+    secureCookie: !isDevelopmentEnvironment,
+  });
+
+  const base = process.env.NEXT_PUBLIC_BASE_PATH ?? "";
+
+  if (!token) {
+    const redirectUrl = encodeURIComponent(new URL(request.url).pathname);
+
+    return NextResponse.redirect(
+      new URL(`${base}/api/auth/guest?redirectUrl=${redirectUrl}`, request.url)
+    );
+  }
+
+  const isGuest = guestRegex.test(token?.email ?? "");
+
+  if (token && !isGuest && ["/login", "/register"].includes(pathname)) {
+    return NextResponse.redirect(new URL(`${base}/`, request.url));
+  }
+
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: [
+    "/",
+    "/chat/:id",
+    "/api/:path*",
+    "/login",
+    "/register",
+
+    "/((?!_next/static|_next/image|favicon.ico|sitemap.xml|robots.txt).*)",
+  ],
+};