feat: complete session — catalog, marketplace, WhatsApp, peer-to-peer, install scripts

Major features:
- Pixel-Perfect glassmorphism design (landing + POS + public catalog)
- OEM/Local catalog toggle with Nexpart taxonomy (14 groups, 108 subgroups, 558 part types)
- Marketplace B2B Phase 1 (bodegas, POs, status machine, WA+email notifications)
- Peer-to-peer inventory (multi-instance, LAN discovery)
- WhatsApp: photo→Vision AI, voice→Whisper, conversational quotations
- Smart unified search (VIN/plate/part_number/keyword auto-detect)
- Shop Supplies tab (vehicle-independent parts)
- Chatbot AI fallback chain (5 models) + response cache
- CSV inventory import tool + setup_instance.sh installer
- Tablet-responsive CSS + sidebar toggle
- Filters, export CSV, employee edit, business data save
- Quotation system (WA→POS) with auto-print on confirmation
- Live stats on landing page

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

pos/services/vin_decoder.py

@@ -14,8 +14,20 @@ def decode_vin(vin):
         return {"error": "VIN debe tener exactamente 17 caracteres alfanumericos (sin I, O, Q)."}
 
     url = f"https://vpic.nhtsa.dot.gov/api/vehicles/DecodeVinValues/{vin}?format=json"
-    resp = requests.get(url, timeout=10)
-    resp.raise_for_status()
+    # NHTSA's free API can be slow (5-30s). Retry once on timeout.
+    import time
+    for attempt in range(2):
+        try:
+            resp = requests.get(url, timeout=25)
+            resp.raise_for_status()
+            break
+        except requests.exceptions.Timeout:
+            if attempt == 0:
+                time.sleep(2)
+                continue
+            return {"error": "El servidor NHTSA no respondio. Intenta de nuevo en unos segundos."}
+        except requests.exceptions.RequestException as e:
+            return {"error": f"Error de conexion con NHTSA: {str(e)[:100]}"}
     data = resp.json()["Results"][0]
 
     error_text = data.get("ErrorText", "") or ""