Correct the FLOWPILOT-MIGRATION.md stale references to a non-existent
ai_sessions.fix_outcome column — the actual implementation added six
columns to session_suggested_fixes. Also fix a stale first-commit SHA
(6721b84 → cdd8bb0, the former was amended away).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>