🐛 fix(build): require regional user defaults

- 🛡️ fail a regional build whose profile lacks `skel`, instead of shipping an ISO that silently skips the advertised input defaults

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

builder/prepare-region.sh

@@ -17,7 +17,8 @@ esac
 
 profile="$runtime/default/regions/$region"
 if [[ ! -f $runtime/bin/omarchy-apply-pacman || ! -f $profile/packages ||
-      ! -f $profile/pacman/pacman.conf.append || ! -f $profile/pacman/mirrorlist.append ]]; then
+      ! -f $profile/pacman/pacman.conf.append || ! -f $profile/pacman/mirrorlist.append ||
+      ! -d $profile/skel ]]; then
   echo "Runtime does not support region '$region'; publish a matching runtime or use --local-source." >&2
   exit 1
 fi