feat: Add MaxUSBDrives parameter for parallel USB drive processing

- Introduced a new parameter `MaxUSBDrives` to control the maximum number of USB drives that can be built in parallel, with a default value of 5.
- Updated UI to include a textbox for setting `MaxUSBDrives`.
- Implemented validation to ensure the value is a non-negative integer.
- Adjusted the deployment function to respect the `MaxUSBDrives` limit during USB drive creation.

FFUDevelopment/FFUUI.Core/FFUUI.Core.psm1

@@ -117,6 +117,7 @@ function Get-GeneralDefaults {
         ShareName                      = "FFUCaptureShare"
         Username                       = "ffu_user"
         Threads                        = 5
+        MaxUSBDrives                   = 5
         BuildUSBDriveEnable            = $false
         CompactOS                      = $true
         Optimize                       = $true