Add a scrollable list to the part GUI for aspect property selection

[Jack-McKalling]

Issue type:

• ➕ Feature request

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Short description:

When clicking the "+" button for an aspect on a cable part, such as an Item Importer from ITunnels, it should provide a scrollable list for all the available properties of that aspect. Exactly how the Logic Programmer does that for all its operators. This will make the GUI slightly more consistent, but a whole lot more user-friendly.

For the same user-friendliness reason, the current left and right buttons for browsing the properties should just be left as-is.

See my manually-painted example:

(the side at which the scrollbar is drawn doesn't matter - I drew it on the left but if the current system draws it on the right that's fine too)

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More info:

This listview-style layout allows the user to directly select any property from the collection without having to browse to it. It would be even better with a hover tooltip on each property to display their expanded description as well as their default and current (if modified) values. Displaying that info would currently not be possible yet.

Initially when opening this GUI, the first property would be automatically selected in the listview, and editable on the right (exactly as current behaviour).

[rubensworks]

Thanks for the suggestion!