Migrated error()/warning() calls across 10 branches to use CLI display API which routes to stderr. 48 files modified across ai_mail, api, backup, daemon, flow, memory, prax, seedgo, spawn, trigger. Seedgo stderr_routing standard created (24th standard) with full-file scanning. System average 49% → 69%. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>