Merge cn-region-switch (with omarchy #13690)

# Conflicts:
#	AGENTS.md
#	bin/omarchy-refresh-pacman
#	default/omarchy/omarchy-menu.jsonc
#	install/post-install/pacman.sh
#	shell/plugins/menu/MenuModel.js
#	test/shell.d/menu-test.sh

shell/plugins/menu/MenuModel.js

@@ -422,7 +422,8 @@ var GUARD_READERS = [
   "omarchy-hyprland-corners",
   "omarchy-hyprland-window-transparency",
   "omarchy-hyprland-workspace-layout-default",
-  "omarchy-language"
+  "omarchy-language",
+  "omarchy-region"
 ]
 
 // Package and command presence account for most of what the guards ask, and