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

scripts/grade_piece_vision.py

@@ -0,0 +1,111 @@
+#!/usr/bin/env python3
+"""A4 CLI — suggest a condition grade for a used (yonke) piece from a photo.
+
+Uses ``services.part_vision`` (QWEN -> Hermes -> OpenRouter). When no vision
+backend answers it prints the returned error and exits non-zero.
+
+Usage (from /home/Autopartes):
+    python3 scripts/grade_piece_vision.py --tenant 28 --piece 300537
+    python3 scripts/grade_piece_vision.py --tenant 28 --piece 300537 --image /ruta/foto.jpg
+    python3 scripts/grade_piece_vision.py --image /ruta/foto.jpg --name "Faro" --dry-run
+    python3 scripts/grade_piece_vision.py --tenant 28 --piece 300537 --apply
+"""
+
+import argparse
+import json
+import os
+import sys
+
+sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)), '..', 'pos'))
+
+
+def _load_env():
+    env_file = '/etc/nexus/pos.env'
+    if os.environ.get('MASTER_DB_URL') or not os.path.exists(env_file):
+        return
+    for line in open(env_file):
+        line = line.strip()
+        if not line or line.startswith('#') or '=' not in line:
+            continue
+        k, v = line.split('=', 1)
+        os.environ.setdefault(k.strip(), v.strip().strip('"').strip("'"))
+
+
+def main():
+    ap = argparse.ArgumentParser(description=__doc__)
+    ap.add_argument('--tenant', type=int, help='tenant id')
+    ap.add_argument('--piece', type=int, help='inventory id of the piece')
+    ap.add_argument('--image', help='image file path (overrides the stored photo)')
+    ap.add_argument('--name', help='piece name for the prompt')
+    ap.add_argument('--category', help='piece category for the prompt')
+    ap.add_argument('--condition', default='usado')
+    ap.add_argument('--apply', action='store_true',
+                    help='persist the suggested grade to inventory.condition_grade')
+    args = ap.parse_args()
+
+    _load_env()
+
+    from services import part_vision
+    from services.image_service import DATA_DIR, STATIC_DIR
+
+    image_bytes = None
+    piece = None
+    conn = None
+
+    try:
+        if args.tenant and args.piece:
+            from tenant_db import get_tenant_conn
+            from services import yonke_service
+            conn = get_tenant_conn(args.tenant)
+            piece = yonke_service.get_piece(conn, args.piece)
+            if not piece:
+                print(json.dumps({'error': 'Piece not found'}))
+                return 1
+
+        if args.image:
+            with open(args.image, 'rb') as fh:
+                image_bytes = fh.read()
+        elif piece:
+            url = piece.get('image_url')
+            for img in piece.get('images') or []:
+                if img.get('is_primary'):
+                    url = img.get('url') or url
+                    break
+            idx = (url or '').find('/images/parts/')
+            if idx != -1:
+                rel = url[idx + len('/images/parts/'):]
+                for base in (DATA_DIR, STATIC_DIR):
+                    path = os.path.join(base, rel)
+                    if os.path.exists(path):
+                        with open(path, 'rb') as fh:
+                            image_bytes = fh.read()
+                        break
+
+        if not image_bytes:
+            print(json.dumps({'error': 'No image available (use --image or a piece with a photo)'}))
+            return 1
+
+        result = part_vision.suggest_grade(
+            image_bytes=image_bytes,
+            name=args.name or (piece or {}).get('name'),
+            category=args.category,
+            condition=args.condition,
+        )
+
+        if args.apply and result.get('condition_grade_suggested') and conn and piece:
+            cur = conn.cursor()
+            cur.execute('UPDATE inventory SET condition_grade = %s WHERE id = %s',
+                        (result['condition_grade_suggested'], piece['id']))
+            conn.commit()
+            cur.close()
+            result['applied'] = True
+
+        print(json.dumps(result, ensure_ascii=False, indent=2))
+        return 0 if result.get('condition_grade_suggested') else 2
+    finally:
+        if conn:
+            conn.close()
+
+
+if __name__ == '__main__':
+    sys.exit(main())