Codebase Quality: Closes issue#13350 Implement AppLifecycleHelper class to improve readability of App.xaml.cs

[jvestell]

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  Closes Code Quality: Break down service registration in App.xaml.cs into granular methods #13350

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[jvestell]

@0x5bfa Service registration order matters. Can I get your feedback here? Ready to build.
@yaira2

[jvestell]

@d2dyno1 Thanks for your comment on the issue itself. Could you look at this PR and be more specific about your comment? Thanks

[d2dyno1]

This class could be made static