define socket protocol for gemini connection

src/app/browser/main/tab/page.cpp

@@ -282,6 +282,10 @@ void Page::navigation_reload(
             Gio::TlsCertificateFlags::NO_FLAGS
         );
 
+        socket__client->set_protocol(
+            Gio::Socket::Protocol::TCP
+        );
+
         socket__client->set_timeout(
             15 // @TODO
         );

src/app/browser/main/tab/page.hpp

@@ -6,6 +6,7 @@
 #include <giomm/outputstream.h>
 #include <giomm/simpleaction.h>
 #include <giomm/simpleactiongroup.h>
+#include <giomm/socket.h>
 #include <giomm/socketclient.h>
 #include <giomm/socketconnection.h>
 #include <glibmm/i18n.h>