fix: rename middleware.ts to proxy.ts (deprecated convention)

src/proxy.ts

@@ -0,0 +1,33 @@
+import { NextResponse } from "next/server";
+import type { NextRequest } from "next/server";
+
+export function middleware(request: NextRequest) {
+  const { pathname } = request.nextUrl;
+
+  // Skip auth check for the health endpoint
+  if (pathname === "/api/health") {
+    return NextResponse.next();
+  }
+
+  const apiKey = process.env.API_KEY;
+
+  // If API_KEY is not configured, skip auth check (fail-open for development)
+  if (!apiKey) {
+    console.warn(
+      "Warning: API_KEY environment variable is not set. API authentication is disabled."
+    );
+    return NextResponse.next();
+  }
+
+  const requestApiKey = request.headers.get("X-API-Key");
+
+  if (!requestApiKey || requestApiKey !== apiKey) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: ["/api/:path*"],
+};