Add 'Remove Apps Folder Content' checkbox to UI and update related logic

- Introduced a new checkbox in the UI for removing application content in the Apps folder after FFU capture.
- Updated the Get-UIConfig function to retrieve the state of the new checkbox.
- Added default value for the new 'RemoveApps' parameter in the general defaults.

FFUDevelopment/FFUUI.Core/FFUUI.Core.psm1

@@ -292,6 +292,7 @@ function Get-GeneralDefaults {
         CleanupDeployISO            = $false
         CleanupDrivers              = $false
         RemoveFFU                   = $false
+        RemoveApps                  = $false # New
         # Hyper-V Settings Defaults
         VMHostIPAddress             = "" # Requires user input
         DiskSizeGB                  = 30