Feature request: "Hub" node

[alessandroperilli]

Almost every day, I find myself wanting a node that:

1. accepts any input (even multiple inputs of the same type)
2. picks the first non-null input as output (similarly to what the Context Switch node does)

For example, right now, I'd really need it to pick the first non-null image among many possible generated by different parts of my workflow and send that image to another node to be saved with metadata readable by A1111/SD.Next/SD Prompt Reader:

Maybe it's the wrong way to think about the flow, but it's very intuitive to me. And I had other use cases for such a node.

Thanks!