Mejoras de sesion: estabilizacion, IA, Nexus Yonke y marketplace B2B

- F0 blindaje: Redis/Celery, pg_hba sin trust LAN, secretos a env 600, backups, webhook auth, jobs muertos
- F1 caja: bugs POS, reembolsos al corte, apartados, CFDI, topes de descuento en cotizacion/apartado
- F2/F7 IA de catalogo: autocategorizacion, dedup de SKUs con embeddings, OCR de facturas, descripciones, claves SAT, limpieza de fitment
- F3 IA en el flujo: vision Yonke, preguntas MeLi, venta cruzada, anomalias, sinonimos, busqueda semantica (rerank/embeddings)
- F4/F8 escala y cartera: /metrics+Prometheus+Grafana, pool, score de credito, churn, metricas multi-tenant
- Nexus Yonke (M1-M6): modelo de datos 1-de-1, alta por donador, vitrina publica, MeLi usado, consignacion, garantia por dias, reportes, etiquetas
- Marketplace B2B entre yonkes (catalogo + pedidos cross-tenant)
- Seguridad: auth en /api/admin/* (35 endpoints), alertas por tenant
- Migraciones v4.27/v4.28; timers expire-demos y rollup-metrics

pos/services/notification_engine.py

@@ -244,7 +244,7 @@ def _send_push(conn, tenant_id, recipient_type, recipient_id, title, body, metad
 def _send_whatsapp(conn, tenant_id, recipient_type, recipient_id, body, metadata):
     """Send WhatsApp notification via existing service."""
     try:
-        from services.whatsapp_service import send_message
+        from services.whatsapp_service import wa_send_text
         cur = conn.cursor()
         phone = None
         if recipient_type == 'customer' and recipient_id:
@@ -255,7 +255,22 @@ def _send_whatsapp(conn, tenant_id, recipient_type, recipient_id, body, metadata
         cur.close()
 
         if phone:
-            send_message(phone, body)
+            # Route via tenant provider (Meta Cloud API / WA CRM or Baileys)
+            cfg = {}
+            try:
+                cur2 = conn.cursor()
+                cur2.execute("SELECT key, value FROM tenant_config WHERE key LIKE 'whatsapp_%' OR key LIKE 'wa_%'")
+                raw = {k: v for k, v in cur2.fetchall()}
+                cur2.close()
+                cfg = {
+                    'provider': raw.get('whatsapp_provider', 'baileys'),
+                    'phone_number_id': raw.get('wa_phone_number_id', ''),
+                    'access_token': raw.get('wa_access_token', ''),
+                    'bridge_url': raw.get('whatsapp_bridge_url', ''),
+                }
+            except Exception:
+                pass
+            wa_send_text(cfg, phone, body)
     except Exception:
         pass