Feature: Mimic UWP's single instance app mode / 功能：模仿 UWP 的单实例应用模式

[JasonWei512]

Current behavior:

When launching a second app instance, show a toast notification that tells user the app is already running, and exit.

New behavior:

When launching a second app instance, redirect activation to the main app instance, and show main instance's app window, just like UWP's default behavior.

Problems:

There's something wrong with GitHub Action's CI builds. When I launch a second instance, RedirectActivationToAsync in Program.cs will crash the app, so main instance's window will not show. The exception message is:

The process was terminated due to an unhandled exception.
Exception Info: System.Runtime.InteropServices.COMException (0x80040155): Interface not registered (0x80040155)

If I compile the app on my PC it works fine.

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当前行为：

启动第二个应用实例时，弹出一条通知告诉用户应用已经在运行，然后退出。

新的行为：

启动第二个应用实例时，把激活重定向到主实例，并显示主实例的窗口，就像 UWP 的默认行为一样。

问题：

GitHub Action 的 CI 构建的包有点问题。启动第二个实例时，Program.cs 中的 RedirectActivationToAsync 会使应用崩溃，所以主实例的窗口不会显示。异常信息为：

The process was terminated due to an unhandled exception.
Exception Info: System.Runtime.InteropServices.COMException (0x80040155): Interface not registered (0x80040155)

在我的电脑上编译就没有这个问题。

[nodew]

I got the same problem when I compile with RedirectActivationToAsync. Do you find out the root cause?

The process was terminated due to an unhandled exception.
Exception Info: System.Runtime.InteropServices.COMException (0x80040155): Interface not registered (0x80040155)

[JasonWei512]

I got the same problem when I compile with RedirectActivationToAsync. Do you find out the root cause?

The process was terminated due to an unhandled exception.
Exception Info: System.Runtime.InteropServices.COMException (0x80040155): Interface not registered (0x80040155)

No yet.

[nodew]

Created an issue at the WindowsAppSDK repo RedirectActivationToAsync throws System.Runtime.InteropServices.COMException: 'Interface not registered (0x80040155)'