The AI was returning 'geopolitical' (the event type/family) instead of
a category name like 'Guerre — Moyen-Orient'. Two fixes:
1. Prompt: rename 'Type' → 'Famille', list categories as CAT_N: "name",
explicit warning not to return a generic type, show valid name examples
2. Code: reject any response that matches a known type string before matching
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>