[Feature] Drag and drop files from explorer into Phoebus to open them

[RobertoRoos]

In my workflow I would like to drag-'n-drop files from Windows explorer into my Phoebus instance to open them.
This is useful when e.g. I'm working out of three folders with very different paths. It's a lot of navigating otherwise.

Currently I can drag files into an open editor. This will for example quickly make an embedded widget, which is quite cool.

I would suggest a feature that dragging a file into these sections causes it to open it:

• An empty home screen
• The startup 'welcome' screen
• The top status and toolbars (always)
• An active, rendered display (any, always)

I'm not entirely sure if is mentioned in the issues already. While searching I found more specific bugs, but I don't think about opening files.