palette.gd / theme_keys.gd already declare `class_name`, so `const Palette =
preload(...)` in every consumer shadowed the global class and emitted 4
editor errors ("has the same name as a global class"). Reference the global
class_names directly. Editor reload now clean; suite 125/125; runtime probe
still builds all 75 showcase nodes with the theme applied.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
