Renumber PXE LAN from 10.9.100.0/24 to 172.16.9.0/24

Single-site bay-stuck issue at WJ: GE Intune Report IP script filters
Get-NetIPAddress on StartsWith("10.") and posts everything matching
to the GE Tines webhook. Bays at WJ get the PXE LAN 10.9.100.x IP
captured and reported -> GE backend tags bays as on a non-corp 10.x
subnet -> dynamic group eligibility for SFLD policy never matches.
Other GE sites work because their PXE LANs aren't on 10.x at all.

Renumber PXE LAN to RFC1918 172.16.9.0/24 so the GE filter naturally
skips wired PXE addresses without any disable-NIC dance.

Server-side already in flight (netplan dual-bound, dnsmasq scope +
boot URL repointed, blancco preferences + grub.cfg + iPXE GetPxeScript
all sed'd to 172.16.9.1). This commit is the playbook / scripts /
docs side: 109 hits across 35 files sed'd in one shot.

After this lands + boot.wim is rebuilt + bays renumber off DHCP,
the 10.9.100.1 binding will be dropped from netplan as the final
cleanup step.

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

scripts/Upload-Image.ps1

@@ -8,15 +8,15 @@
 #   .\Upload-Image.ps1                              (selected OS + packages, no drivers)
 #   .\Upload-Image.ps1 -IncludeDrivers              (also upload selected hardware drivers)
 #   .\Upload-Image.ps1 -CachePath "D:\MCL\Cache"    (custom cache location)
-#   .\Upload-Image.ps1 -Server 10.9.100.1           (custom server IP)
+#   .\Upload-Image.ps1 -Server 172.16.9.1           (custom server IP)
 #
-# After upload, use the PXE webapp (http://10.9.100.1:9009) to import
+# After upload, use the PXE webapp (http://172.16.9.1:9009) to import
 # the uploaded content into the desired image type.
 #
 
 param(
     [string]$CachePath = "C:\ProgramData\GEAerospace\MediaCreator\Cache",
-    [string]$Server = "10.9.100.1",
+    [string]$Server = "172.16.9.1",
     [string]$User = "pxe-upload",
     [string]$Pass = "pxe",
     [switch]$IncludeDrivers