Allow custom parameters in Start node (and show them in "Execute Workflow")

According to the documentation of the nodes “Start” and “Execute Workflow”, these seem to be very tightly coupled.

However, it is quite hard to prepare the data for the workflow.

It would be awesome, if we could declare expected parameters on the “Start” node along with default values and these would mirror on the “Execute Workflow” node.

I think it should something similar to the “Set” node.

Or maybe if we could create some kind of documentation on the workflow defining which values is expected for the workflow, and when you call this workflow through the workflow node it will show this documentation.

@rodrigoscdc @rodrigoscdc this would be quite handy. Please me sure you upvote the feature request.