Append gateway from multiple sources

[till-stadtler]

Is your feature request related to a problem? Please describe.

When working on BPMN models live in front of an audience, I want to make changes to multiple elements at once to be quicker. When reviewing and redesigning BPMN models, I want to save time by:
Selecting multiple elements and then create a merging exclusive gateway with one action.

Describe the solution you'd like

When selecting multiple elements, it is currently possible to rearrange the elements (if no sequence flow is selected) and to change the color of all selected elements via the context menu.

I would like to have the option in the context pad to append a gateway to the selected elements, resulting in one merging gateway with multiple incoming sequence flows, one from each selected element.

Describe alternatives you've considered

The alternative is the current way of modeling:
Create a gateway from one of the elements, then select each of the other elements to draw a sequence flow to the gateway.

Additional context

Allow appending of gateway when selecting multiple elements that all allow appending a gateway indicidually:

Example result:

[barmac]

I moved this to the backlog for now.