fix(dev): share auth across dev frontend proxy

src/components/microservices/k3sctl-adapter/src/index.ts

@@ -95,12 +95,29 @@ const nativeServiceFailures = new Map<string, number>();
 const nativeServiceEndpointCache = new Map<string, { endpoint: NativeServiceEndpoint; expiresAt: number }>();
 const nativeServiceTunnels = new Map<string, NativeServiceTunnel>();
 logWriter?.prune();
+const forwardedResponseHeaderNames = [
+  "cache-control",
+  "content-disposition",
+  "etag",
+  "expires",
+  "last-modified",
+  "location",
+  "set-cookie",
+  "www-authenticate",
+] as const;
 
 function envString(name: string, fallback: string): string {
   const value = process.env[name];
   return value === undefined || value.length === 0 ? fallback : value;
 }
 
+function copyForwardedResponseHeaders(from: Headers, to: Headers): void {
+  for (const name of forwardedResponseHeaderNames) {
+    const value = from.get(name);
+    if (value !== null && value.length > 0) to.set(name, value);
+  }
+}
+
 function envNumber(name: string, fallback: number): number {
   const raw = process.env[name];
   if (raw === undefined || raw.trim().length === 0) return fallback;
@@ -636,17 +653,19 @@ async function fetchNativeServiceUrl(
       signal: controller.signal,
     });
     const body = await boundedText(upstream, 8 * 1024 * 1024);
+    const responseHeaders = new Headers({
+      "content-type": upstream.headers.get("content-type") ?? "application/octet-stream",
+      "x-unidesk-proxy-mode": "kubernetes-native-service",
+      "x-unidesk-k3s-service": service.id,
+      "x-unidesk-k3s-service-url": upstreamUrl.origin,
+      "x-unidesk-upstream-duration-ms": String(Date.now() - startedAt),
+      "x-unidesk-response-truncated": body.truncated ? "true" : "false",
+      ...extraHeaders,
+    });
+    copyForwardedResponseHeaders(upstream.headers, responseHeaders);
     return new Response(body.text, {
       status: upstream.status,
-      headers: {
-        "content-type": upstream.headers.get("content-type") ?? "application/octet-stream",
-        "x-unidesk-proxy-mode": "kubernetes-native-service",
-        "x-unidesk-k3s-service": service.id,
-        "x-unidesk-k3s-service-url": upstreamUrl.origin,
-        "x-unidesk-upstream-duration-ms": String(Date.now() - startedAt),
-        "x-unidesk-response-truncated": body.truncated ? "true" : "false",
-        ...extraHeaders,
-      },
+      headers: responseHeaders,
     });
   } finally {
     clearTimeout(timer);