Codemod (editor/scripts/migrate-compat-colors.mjs) rewrites every var(--legacy)
reference to the canonical --c-* token it maps to in compat.css (1:1 aliases
only; computed color-mix/fallback aliases left in place). 218 files, 1947
references. Pure rename — compat.css already guarantees each alias equals its
--c-* target, so no behaviour change.