Adds Windows Media Source selection options

Introduces radio buttons to choose between downloading a Windows ESD or providing a custom Windows ISO file, enhancing flexibility for media source selection. Updates configuration handling and event listeners to toggle visibility and appropriately populate combo boxes based on the selected media source.

FFUDevelopment/FFUUI.Core/FFUUI.Core.Config.psm1

@@ -54,6 +54,7 @@ function Get-UIConfig {
         InstallOffice                  = $State.Controls.chkInstallOffice.IsChecked
         InstallWingetApps              = $State.Controls.chkInstallWingetApps.IsChecked
         ISOPath                        = $State.Controls.txtISOPath.Text
+        WindowsMediaSource             = if ($null -ne $State.Controls.rbProvideISO -and $State.Controls.rbProvideISO.IsChecked) { "Provide Windows ISO" } else { "Download Windows ESD" }
         LogicalSectorSizeBytes         = [int]$State.Controls.cmbLogicalSectorSize.SelectedItem.Content
         # Make                           = $null
         MediaType                      = $State.Controls.cmbMediaType.SelectedItem
@@ -486,6 +487,15 @@ function Update-UIFromConfig {
 
     # Windows Settings
     Set-UIValue -ControlName 'txtISOPath' -PropertyName 'Text' -ConfigObject $ConfigContent -ConfigKey 'ISOPath' -State $State
+    # Load Windows Media Source setting
+    if ($null -ne $ConfigContent.PSObject.Properties.Item('WindowsMediaSource')) {
+        if ($ConfigContent.WindowsMediaSource -eq 'Provide Windows ISO') {
+            $State.Controls.rbProvideISO.IsChecked = $true
+        }
+        else {
+            $State.Controls.rbDownloadESD.IsChecked = $true
+        }
+    }
     
     # Special handling for Windows Release and SKU due to value collision (e.g., 2019 for Server and LTSC)
     if (($null -ne $ConfigContent.PSObject.Properties.Item('WindowsRelease')) -and ($null -ne $ConfigContent.PSObject.Properties.Item('WindowsSKU'))) {