refactor: Move recipe generator to cook/ directory and fix flattening bugs

- Move recipe-generator/ to cook/ for cleaner structure

- Fix ksflatten-relative path conversion to handle all %include paths

- Fix validation exit code to only fail on actual errors

- All recipes now generate and flatten successfully via make all

cook/ingredients/packages/fedora-remix.ks

@@ -0,0 +1,18 @@
+#            __          ____                        ____  _____
+#     ____  / /_  __  __/ / /___  ____ ___  ___     / __ \/ ___/
+#    / __ \/ __ \/ / / / / / __ \/ __ `__ \/ _ \   / / / /\__ \
+#   / /_/ / / / / /_/ / / / /_/ / / / / / /  __/  / /_/ /___/ /
+#  / .___/_/ /_/\__, /_/_/\____/_/ /_/ /_/\___/   \____//____/
+# /_/          /____/
+
+# Packages to be used to create a Fedora Remix and comply Fedora Remix legal guidelines: https://fedoraproject.org/wiki/Remix
+
+%packages --exclude-weakdeps
+
+fedora-remix-logos # Fedora Remix logos
+generic-release # Generic release files
+generic-logos # Icons and pictures
+generic-release-common # Generic release files
+generic-release-notes # Release Notes
+
+%end # End of the packages section