Shopfloor: auto-register 9999-placeholder machine number prompt

If a bay is imaged with the 9999 placeholder (tech leaves the WinPE
prompt blank or types 9999), the lockdown+auto-login chain ends up at
the ShopFloor user with no real machine number. We had Check-MachineNumber.ps1
written - InputBox + Update-MachineNumber pulls per-machine NTLARS .reg
+ udc_settings_<N>.json from the SFLD share - but it only got registered
when a tech manually ran Configure-PC + toggled item 6. Fresh 9999 bays
never got the prompt, leaving the bay stuck on placeholder values until
someone noticed.

New Register-CheckMachineNumberTask.ps1 auto-registers the logon task
at imaging time. Gated on C:\Enrollment\machine-number.txt == 9999;
bays imaged with a real number never get the task (and any stale task
from a prior 9999-imaging on the same disk is cleaned up).

Wired into Run-ShopfloorSetup.ps1 right after the S: drive logon mapper
register. Skipped for self-contained types (display kiosks have no
machine number).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

playbook/shopfloor-setup/Run-ShopfloorSetup.ps1

@@ -360,6 +360,26 @@ if ($noEnforceTypes -contains $pcType) {
     Write-Host "Register-MapSfldShare.ps1 not found (optional) - skipping"
 }
 
+# --- Check Machine Number logon prompt ---
+# Auto-register the "Check Machine Number" scheduled task. Bays imaged with
+# the 9999 placeholder will prompt the first ShopFloor end-user logon to
+# enter the real machine number; on success Update-MachineNumber.ps1 pulls
+# the per-machine NTLARS .reg + UDC settings JSON + UDC data backup from
+# SFLD and the task self-unregisters. Self-disables once the number is
+# real, so safe to always register here.
+# Skipped for self-contained types (Display) that have no machine number.
+$registerCheckMN = Join-Path $setupDir 'Shopfloor\Register-CheckMachineNumberTask.ps1'
+if ($noEnforceTypes -contains $pcType) {
+    Write-Host ""
+    Write-Host "=== Skipping Check Machine Number task ($pcType has no machine number) ==="
+} elseif (Test-Path -LiteralPath $registerCheckMN) {
+    Write-Host ""
+    Write-Host "=== Registering Check Machine Number logon task ==="
+    try { & $registerCheckMN } catch { Write-Warning "Check-MachineNumber registration failed: $_" }
+} else {
+    Write-Host "Register-CheckMachineNumberTask.ps1 not found (optional) - skipping"
+}
+
 # --- Run enrollment (PPKG install) ---
 # Enrollment is the LAST thing we do. Install-ProvisioningPackage triggers
 # an immediate reboot -- everything after this call is unlikely to execute.