Update widgets for iOS 17

[bdbergeron]

With iOS 17, Apple made some significant changes to widgets, including adding a default content margin and introducing new placements, such as StandBy on iPhone, Lock Screen on iPad, and desktop on macOS. When building the current app against the iOS 17 SDK, the widgets now have extra padding. I thought I'd take a stab at updating them to accommodate both the new content margins and placements.

Relevant information: https://developer.apple.com/documentation/widgetkit/preparing-widgets-for-additional-contexts-and-appearances

Apologies for the sizable PR here - the core functionality and design of the widgets remain untouched. In order to make the widgets work flawlessly with Xcode Previews and the Widget Context Variants view, I organized the code a bit and split up the models and views from the widget configuration declaration files. I hope you'll find this to be a cleaner workspace.

iOS 16 Home Screen	iOS 17 Home Screen

iOS 16 Lock Screen	iOS 17 Lock Screen

iOS 17 StandBy Mode

iPad Lock Screen

[bdbergeron]

Hey @daneden, now that the current version in the App Store is built against the iOS 17 SDK, what are your thoughts on these updates?

Current	Updated

StandBy

[bdbergeron]

Thanks @daneden! Appreciate the kind words, too. Really appreciate this app, happy to help you out with it in any way I can!