Mark the installer batch files that need administrator rights with -Admin

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

seediso/windows11/build-seed.sh

@@ -21,7 +21,7 @@ seed_files=(
   "$work_dir/Autounattend.xml"
   "$script_dir/Configure-Windows.ps1"
 )
-# Numbered installer scripts (10-Install-Git.bat, 20-..., in install order).
+# Numbered installer scripts (10-Install-Git-Admin.bat, 20-..., in install order).
 shopt -s nullglob
 seed_files+=("$script_dir"/[0-9][0-9]-*.bat)
 shopt -u nullglob