fix(ext/node): pass content-disposition header as string instead of bytes (#25128)

Closes https://github.com/denoland/deno/issues/25117

ext/node/polyfills/http.ts

@@ -906,7 +906,7 @@ class ClientRequest extends OutgoingMessage {
     // https://www.rfc-editor.org/rfc/rfc6266#section-4.3
     // Refs: https://github.com/nodejs/node/pull/46528
     if (isContentDispositionField(key) && this._contentLength) {
-      value = Buffer.from(value, "latin1");
+      value = Buffer.from(value).toString("latin1");
     }
 
     if (Array.isArray(value)) {

tests/unit_node/http_test.ts

@@ -1559,3 +1559,30 @@ Deno.test("[node/http] req.url equals pathname + search", async () => {
 
   await promise;
 });
+
+Deno.test("[node/http] ClientRequest content-disposition header works", async () => {
+  const payload = Buffer.from("hello world");
+  let body = "";
+  let headers = {} as http.IncomingHttpHeaders;
+  const { promise, resolve, reject } = Promise.withResolvers<void>();
+  const req = http.request("http://localhost:4545/echo_server", {
+    method: "PUT",
+    headers: {
+      "content-disposition": "attachment",
+    },
+  }, (resp) => {
+    headers = resp.headers;
+    resp.on("data", (chunk) => {
+      body += chunk;
+    });
+
+    resp.on("end", () => {
+      resolve();
+    });
+  });
+  req.once("error", (e) => reject(e));
+  req.end(payload);
+  await promise;
+  assertEquals(body, "hello world");
+  assertEquals(headers["content-disposition"], "attachment");
+});