#642 made usage of Node::Subscribe with lambdas worse

[jmachowinski]

Environment

• OS Version: Ubuntu 26.04
• Source or binary build?
  Source jetty build

Description

The changes introduced in #642 made the subscription API substantially worse if using lambdas.

Before the changes one could do

gzNode->Subscribe<gz::msgs::CameraInfo>( topic, [](
     const gz::msgs::CameraInfo& gzMsg) { });

if you are using lambdas now,

// NOT COMPILING
gzNode->Subscribe( topic, [](const gz::msgs::CameraInfo& gzMsg) { });

fails as the deduction for lambda argument fails, therefore one needs to do

gzNode->Subscribe( topic, [](
  std::function<void(const gz::msgs::CameraI&)>{const gz::msgs::CameraInfo& gzMsg) { }});

This is a clear step backwards in the usability of the API.