Don't copy every byte read into arena

src/connection.hpp

@@ -349,7 +349,7 @@ private:
                   ConnectionHandler *handler, std::weak_ptr<Server> server);
 
   // Networking interface - only accessible by Server
-  std::string_view readBytes(size_t max_request_size, size_t buffer_size);
+  std::string_view readBytes(char *buf, size_t buffer_size);
   bool writeBytes();
   void tsan_acquire();
   void tsan_release();