Fix memory leak: copy bind_address_storage to webserver

The webserver was only copying the raw bind_address pointer but not the
shared_ptr that owns the storage. This caused the memory to be freed
when the temporary create_webserver was destroyed, leaving webserver
with a dangling pointer and causing valgrind to report a leak.

Author: etr

src/httpserver/webserver.hpp

@@ -144,6 +144,7 @@ class webserver {
      validator_ptr validator;
      unescaper_ptr unescaper;
      const struct sockaddr* bind_address;
+     std::shared_ptr<struct sockaddr_storage> bind_address_storage;
      /* Changed type to MHD_socket because this type will always reflect the
      platform's actual socket type (e.g. SOCKET on windows, int on unixes)*/
      MHD_socket bind_socket;

src/webserver.cpp

@@ -134,6 +134,7 @@ webserver::webserver(const create_webserver& params):
     validator(params._validator),
     unescaper(params._unescaper),
     bind_address(params._bind_address),
+    bind_address_storage(params._bind_address_storage),
     bind_socket(params._bind_socket),
     max_thread_stack_size(params._max_thread_stack_size),
     use_ssl(params._use_ssl),