Proposal: Add XamlGeneratedMain entry point for Windows.UI.Xaml(Modern .NET)

[Gaoyifei1011]

Summary

为 Windows.UI.Xaml(Modern .NET) 添加 XamlGeneratedMain 入口点

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Add XamlGeneratedMain entry point for Windows.UI.Xaml(Modern .NET)

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Currently, the entry point for WinUI 3 apps in the Windows App SDK has been updated, adding the XamlGeneratedProgram.XamlGeneratedMain(); entry point, but UWP still hasn’t been updated. Hopefully, this entry point for UWP will be updated in the future.

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目前 Windows App SDK 的 WinUI 3 应用入口点已经更新，添加了 XamlGeneratedProgram.XamlGeneratedMain(); 入口点， 但是 UWP 仍然没有更新，希望未来能对 UWP 的这一入口点进行更新

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Rationale

microsoft/microsoft-ui-xaml#11245

Important Notes

microsoft/microsoft-ui-xaml#11245

Open Questions

microsoft/microsoft-ui-xaml#11245