feat(whatsapp): QWEN primary AI backend, Hermes fallback, conversation history, vehicle persistence, demo prompts

- Add QWEN (qwen3.6) as primary AI backend with short system prompt
- Hermes remains as fallback with 45s timeout
- Increase QWEN timeout to 35s, max_tokens to 4000
- Add conversation history loading from whatsapp_messages (last 4 msgs)
- Persist detected vehicle in whatsapp_sessions table
- Add 'limpiar chat' / 'nuevo chat' / 'reset' commands to clear history
- Fix CSS conflict: rename whatsapp chat-panel classes to wa-chat-panel
- Fix JS ID conflicts with chat.js widget (waChatPanel, waChatMessages, etc.)
- Improve no-stock response: conversational with alternatives
- Split search_query by | for multi-part lookups
- Add DEMO_PROMPTS.md and DEMO_PROMPTS_V2.md

pos/blueprints/inventory_bp.py

@@ -1360,36 +1360,55 @@ def auto_match_item_vehicles(item_id):
     part_number, brand, name = row
     compat_source = get_compat_source(g.tenant_id)
 
+    tecdoc_result = None
+    qwen_result = None
+
     # TecDoc auto-match
     if compat_source in ('tecdoc', 'both'):
         master = get_master_conn()
         try:
-            result = auto_match_vehicle_compatibility(master, conn, item_id, part_number,
-                                                       brand=brand, name=name)
-            return jsonify(result)
+            tecdoc_result = auto_match_vehicle_compatibility(master, conn, item_id, part_number,
+                                                              brand=brand, name=name)
         finally:
             master.close()
-            conn.close()
 
     # QWEN AI auto-match
-    if compat_source == 'qwen':
+    if compat_source in ('qwen', 'both'):
         try:
             from services.qwen_fitment import get_vehicle_fitment
             from services.inventory_vehicle_compat import save_qwen_fitment
             fitment = get_vehicle_fitment(part_number, name, brand)
             inserted = save_qwen_fitment(conn, item_id, fitment)
-            conn.close()
-            return jsonify({
-                'matched': inserted > 0,
+            qwen_myes = [v['mye_id'] for v in fitment.get('vehicles', []) if v.get('mye_id')]
+            qwen_result = {
+                'matched': len(qwen_myes) > 0,
                 'matches': [],
-                'myes': [v['mye_id'] for v in fitment.get('vehicles', []) if v.get('mye_id')],
+                'myes': qwen_myes,
                 'inserted': inserted,
-            })
+                'total_qwen': len(qwen_myes),
+                'confidence': fitment.get('confidence', 0),
+                'notes': fitment.get('notes', ''),
+            }
         except Exception as e:
-            conn.close()
-            return jsonify({'error': str(e)}), 500
+            qwen_result = {'error': str(e)}
 
     conn.close()
+
+    # Return combined or single-source result
+    if compat_source == 'both':
+        return jsonify({
+            'tecdoc': tecdoc_result,
+            'qwen': qwen_result,
+            'matched': bool(
+                (tecdoc_result and tecdoc_result.get('matched'))
+                or (qwen_result and qwen_result.get('matched'))
+            ),
+        })
+    if compat_source == 'tecdoc':
+        return jsonify(tecdoc_result)
+    if compat_source == 'qwen':
+        return jsonify(qwen_result)
+
     return jsonify({'error': 'No compatibility source configured'}), 400