Include C# samples and Narrator considerations in App Instancing documentation

[adrastogi]

1. The code samples in this documentation are written in C++. It would be great to also include references for C# developers as well.
2. In particular for C# apps, the samples call out a caveat regarding how to implement single instancing support in a specific way to avoid breaking Narrator. This would be good to call out explicitly in the documentation (along with explaining why making the main method async breaks Narrator).

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Document Details

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• ID: 165dd8a4-727f-7789-4bb2-fb98bd76380b
• Version Independent ID: d362e3da-c88c-a4d7-c51d-dd9d98487c2a
• Content: App instancing with the app lifecycle API (Windows App SDK) - Windows apps
• Content Source: hub/apps/windows-app-sdk/applifecycle/applifecycle-instancing.md
• Product: reunion
• Technology: app-lifecycle
• GitHub Login: @hickeys
• Microsoft Alias: hickeys

[alvinashcraft]

Hi @adrastogi. We have a new page on creating single instanced apps now, and I believe this uses a method that won't break Narrator. Let me know if this new page meets your needs.

Thanks for your feedback.