fix: Prevent HttpRequest from being closed

In case a stream the request is being piped into closes,
we don't want to close the request since it shares a socket
with the response.

src/server/HttpRequest.ts

@@ -5,3 +5,10 @@ import type { Guarded } from '../util/GuardedStream';
  * An incoming HTTP request;
  */
 export type HttpRequest = Guarded<IncomingMessage>;
+
+/**
+ * Checks if the given stream is an HttpRequest.
+ */
+export function isHttpRequest(stream: any): stream is HttpRequest {
+  return typeof stream.socket === 'object' && typeof stream.url === 'string' && typeof stream.method === 'string';
+}