Make HTTPServer ignore responses that cannot be sent

src/http/lifecycle/Response.ts

@@ -255,6 +255,14 @@ export class Response {
         await this.sent$.next(this)
     }
 
+    /**
+     * Returns true if the response can still be sent. False if it has been sent
+     * or the connection has been destroyed.
+     */
+    public canSend(): boolean {
+        return !(this.responseEnded || this.serverResponse.destroyed)
+    }
+
     /**
      * Mark the response as ended and close the socket.
      */