fix(pos): chatbot busca partes automaticamente con traduccion ES→EN

- System prompt: SIEMPRE devuelve search_query en ingles
- Diccionario de traducciones (balatas→Brake Pad, etc.)
- Busca directo sin preguntar mas info
- Fallback: extrae keywords si AI no da search_query

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pos/blueprints/chat_bp.py

@@ -46,10 +46,23 @@ def chat():
             vehicle_match = _resolve_vehicle(master, vehicle)
 
         # Run catalog search if we have a search query
-        if search_query and master and tenant:
+        # Also search if AI identified a vehicle but didn't give a search_query
+        effective_query = search_query
+        if not effective_query and vehicle:
+            # Extract likely part keywords from the user's message
+            import re
+            # Remove brand/model/year from message to get the part description
+            part_words = user_message.lower()
+            for remove in [vehicle.get('brand',''), vehicle.get('model',''), str(vehicle.get('year',''))]:
+                part_words = part_words.replace(remove.lower(), '')
+            part_words = re.sub(r'necesito|quiero|busco|para|un|una|el|la|de|del|los|las|mi|\d{4}', '', part_words).strip()
+            if len(part_words) >= 3:
+                effective_query = part_words
+
+        if effective_query and master and tenant:
             try:
                 results = catalog_service.smart_search(
-                    master, search_query, tenant, branch_id, limit=10
+                    master, effective_query, tenant, branch_id, limit=10
                 )
                 search_results = results if results else []
             except Exception: