Add robust sanitization for names used in paths

Introduces a new common function, `ConvertTo-SafeName`, to sanitize strings by removing characters that are invalid in Windows file paths.

This function is now used consistently when creating directory and file names for drivers (Dell, HP, Lenovo, Microsoft) and applications to prevent path-related errors. It replaces several ad-hoc sanitization methods with a single, more robust implementation.

FFUDevelopment/BuildFFUVM.ps1

@@ -904,8 +904,10 @@ function Get-MicrosoftDrivers {
                 New-Item -Path $DriversFolder -ItemType Directory -Force | Out-Null
                 WriteLog "Drivers folder created"
             }
+            $sanitizedModel = ConvertTo-SafeName -Name $Model
+            if ($sanitizedModel -ne $Model) { WriteLog "Sanitized model name: '$Model' -> '$sanitizedModel'" }
             $surfaceDriversPath = Join-Path -Path $DriversFolder -ChildPath $Make
-            $modelPath = Join-Path -Path $surfaceDriversPath -ChildPath $Model
+            $modelPath = Join-Path -Path $surfaceDriversPath -ChildPath $sanitizedModel
             if (-Not (Test-Path -Path $modelPath)) {
                 WriteLog "Creating model folder: $modelPath"
                 New-Item -Path $modelPath -ItemType Directory | Out-Null