The four checkbox PNGs were incorrectly identified as unused.
They are referenced at lines 6, 9, 10, and 12 of
resources/themes/kalulu_theme.tres, which is the globally applied
custom theme (project.godot). Restoring them to avoid broken
checkbox icons and theme load failures.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>