Re-copy .opencode/skills/impeccable from upstream tag skill-v4.6.0
(8a0e198, engine 0.1.15), keep LICENSE, and re-apply the OmO path
rewrite and the critique routing line.
The documented rewrite missed the base-directory fallback in SKILL.md,
which ends at scripts rather than scripts/impeccable, so the upgrade
command now rewrites the scripts directory prefix. The skills README
also notes that the engine binary is downloaded by scripts/VERSION
rather than vendored.
David Ibia