Feature request: Add support to open .opossum files with double-click

[abraemer]

Is your feature request related to a problem? Please describe.
Currently, to open an opossum file, I need to first open OpossumUI, select 'Open File' and then navigate to the file in the dialog.

Describe the solution you'd like
It would be much simpler to be able to just double-click the opossum file to open it in OpossumUI.

Additional context
Currently, one can associate OpossumUI with .opossum files but that does not work as expected: Double-clicking a .opossum file just opens OpossumUI but does not load the file. I think this is because OpossumUI does not consider CLI args.

I think double-click just executes something like OpossumUI path/to/file. So all that is required for this QoL feature is to check for a CLI argument and if it exists and looks like a path load that file.