Closes the gap where /codex's synthesis recommendation was only checked
statically (template grep) and via fixtures. Drives the real /codex skill over
a flawed diff and grades the emitted "Recommendation: ... because ..." line
with judgeRecommendation (present/commits/has_because/substance>=4). The named
weak spot holds up: substance 5. Periodic tier.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Garry Tan