[Refactor]Port C++/CX to C++/WinRT (#34198)

## Summary of the Pull Request
Removes all C++/CX code, replacing it with C++/WinRT.

## Detailed Description of the Pull Request / Additional comments
Removes all C++/CX code.
Renames interop namespaces to be better consumed by CsWinRT.
Standardizes all projects on net8.0-windows10.0.20348.0, which is a
requirement for C++/WinRT usage.
FileLocksmithLibInterop brought to stdcpplatest and static analysis
errors were corrected.
Removed now unneeded string conversion code from
FileLocksmithLibInterop.
Changed interop KeyboardHook to use a single hook across all instances.
Required because on C++/WinRT we don't have the .NET runtime to bind a
object instance to a delegate and be able to pass it to a C function
pointer argument (still no idea why this worked correctly on C++/CX to
be honest). This change actually makes us create less low level keyboard
hooks.
Changed some code that depended on arrays since WinRT/C++ returns null
instead of an empty array through the interface.

## Validation Steps Performed
Built and tested runtime.

src/modules/launcher/Plugins/Microsoft.PowerToys.Run.Plugin.System/Microsoft.PowerToys.Run.Plugin.System.csproj

@@ -3,7 +3,7 @@
 
   <PropertyGroup>
     <OutputType>Library</OutputType>
-    <TargetFramework>net8.0-windows</TargetFramework>
+    <TargetFramework>net8.0-windows10.0.20348.0</TargetFramework>
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Microsoft.PowerToys.Run.Plugin.System</RootNamespace>
     <AssemblyName>Microsoft.PowerToys.Run.Plugin.System</AssemblyName>
@@ -34,6 +34,7 @@
   </ItemGroup>
 
   <ItemGroup>
+    <PackageReference Include="Microsoft.Windows.CsWinRT" />
     <PackageReference Include="System.Diagnostics.EventLog">
       <!-- This package is a dependency of Microsoft.Extensions.Logging.EventLog, but we need to set it here so we can exclude the assets, so it doesn't conflict with the 8.0.1 dll coming from .NET SDK. -->
       <ExcludeAssets>runtime</ExcludeAssets> <!-- Should already be present on .net sdk runtime, so we avoid the conflicting runtime version from nuget -->