FindPackagesByPackageFamily is unable to find wasdk 1.8 packages

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### Describe the bug

I found out that all my packaged app that has been upgraded to wasdk 1.8 all stops working on older windows 10 (windows 10 17763 to be exact). After some debugging, it seems that the win32 api `FindPackagesByPackageFamily()` did not find the package, causing the `DeploymentManager` initializer to fail (which is by default enabled for some reason). And as a result, the app crashed immediately upon launch, not even able to leave a dump

However, I can confirm the package DO exist.

and the same call is able to find the package under windows 11.

A temporary solution I found is just disable auto-initializer in the `vcxproj`, and I am not sure about what will this affect from [this documentation](https://learn.microsoft.com/en-us/windows/apps/package-and-deploy/project-properties)

### Steps to reproduce the bug

1. Create a winui3 project using the C++ winui3 packaged project template in Visual Studio 2026.
2. Run and debug under windows 10.

### Expected behavior

_No response_

### Screenshots

_No response_

### NuGet package version

Windows App SDK 1.8.3: 1.8.251106002

### Packaging type

Packaged (MSIX)

### Windows version

Windows 10 version 1809 (17763, October 2018 Update)

### IDE

_No response_

### Additional context

Visual Studio 2026

**I also tested the default C# project template and it has the same issue. Both crashed immediately upon launch.**

Start by reproducing the packaged C++ and C# template projects on Windows 10 version 1809 (17763) with Windows App SDK 1.8.3. Trace the DeploymentManager initializer and its FindPackagesByPackageFamily call, then compare the behavior with Windows 11 and the vcxproj configuration. Done means the package is found and the app launches on Windows 10 with the auto-initializer enabled.

Written by the indexing model from the issue text.