Tunnel node

The tunnel sender node sends whatever you connect to it to all the tunnel receiver nodes with the same key. Here's how it works in Pixel Composer:

https://github.com/user-attachments/assets/90bdaa8c-a962-4837-9932-26656be1038f

It helps a lot when trying to manage a lot of long and crossing connections, like this:

Some improvements to Pixel Composer's implementation can be made, such as making the tunnel receiver node use a combo box dropdown menu that's automatically populated from all the senders' keys.