[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/previewpane/GcodePreviewHandler/Program.cs

@@ -5,7 +5,7 @@
 using System.Globalization;
 using System.Windows.Threading;
 using Common.UI;
-using interop;
+using PowerToys.Interop;
 
 namespace Microsoft.PowerToys.PreviewHandler.Gcode
 {

src/modules/previewpane/MarkdownPreviewHandler/Program.cs

@@ -5,7 +5,7 @@
 using System.Globalization;
 using System.Windows.Threading;
 using Common.UI;
-using interop;
+using PowerToys.Interop;
 
 namespace Microsoft.PowerToys.PreviewHandler.Markdown
 {

src/modules/previewpane/MonacoPreviewHandler/Program.cs

@@ -5,8 +5,8 @@
 using System.Globalization;
 using System.Windows.Threading;
 using Common.UI;
-using interop;
 using ManagedCommon;
+using PowerToys.Interop;
 
 namespace Microsoft.PowerToys.PreviewHandler.Monaco
 {

src/modules/previewpane/PdfPreviewHandler/Program.cs

@@ -4,7 +4,7 @@
 using System.Globalization;
 using System.Windows.Threading;
 using Common.UI;
-using interop;
+using PowerToys.Interop;
 
 namespace Microsoft.PowerToys.PreviewHandler.Pdf
 {

src/modules/previewpane/QoiPreviewHandler/Program.cs

@@ -5,7 +5,7 @@
 using System.Globalization;
 using System.Windows.Threading;
 using Common.UI;
-using interop;
+using PowerToys.Interop;
 
 namespace Microsoft.PowerToys.PreviewHandler.Qoi
 {

src/modules/previewpane/SvgPreviewHandler/Program.cs

@@ -5,7 +5,7 @@
 using System.Globalization;
 using System.Windows.Threading;
 using Common.UI;
-using interop;
+using PowerToys.Interop;
 
 namespace Microsoft.PowerToys.PreviewHandler.Svg
 {

src/modules/previewpane/UnitTests-PreviewHandlerCommon/UnitTests-PreviewHandlerCommon.csproj

@@ -9,7 +9,7 @@
   <PropertyGroup>
     <ProjectGuid>{748417CA-F17E-487F-9411-CAFB6D3F4877}</ProjectGuid>
     <RootNamespace>PreviewHandlerCommonUnitTests</RootNamespace>
-    <TargetFramework>net8.0-windows</TargetFramework>
+    <TargetFramework>net8.0-windows10.0.20348.0</TargetFramework>
     <ProjectTypeGuids>{3AC096D0-A1C2-E12C-1390-A8335801FDAB};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
     <VSToolsPath Condition="'$(VSToolsPath)' == ''">$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v$(VisualStudioVersion)</VSToolsPath>
     <ReferencePath>$(ProgramFiles)\Common Files\microsoft shared\VSTT\$(VisualStudioVersion)\UITestExtensionPackages</ReferencePath>

src/modules/previewpane/common/PreviewHandlerCommon.csproj

@@ -14,7 +14,7 @@
 
   <PropertyGroup>
     <ProjectGuid>{AF2349B8-E5B6-4004-9502-687C1C7730B1}</ProjectGuid>
-    <TargetFramework>net8.0-windows</TargetFramework>
+    <TargetFramework>net8.0-windows10.0.20348.0</TargetFramework>
     <AssemblyName>PowerToys.PreviewHandlerCommon</AssemblyName>
   </PropertyGroup>