Create App Icon picker for new .icon files

[dfsm]

iOS26 brings with it new app icon files.

Spanky has provided some, though there is currently no way to select them as the original Picker does not apply!

The app icons are so different that the existing picker doesn't work at all.
Also, in order to get the new .icon versions working while posting to App Store Connect, the old App Icon assets file and references had to be removed from the project.

So either a new picker needs to be created or the existing one updated to handle the new .icon files.

In the meantime, I am setting individual icon files in the project settings as its default icon. App Store Connect rejected the Ghost v2.icon file due to some kind of transparency issue, so will need to request another version of that.

[dfsm]

The existing picker might work if the new icons and old icons are present and share the same names...
App Store Connect is currently refusing all builds that contain the new .icon files, though. As of beta 3