- 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
- Add thermal_printer.py service generating raw ESC/POS bytes for 58mm/80mm printers
- Add /pos/api/sales/<id>/print endpoint (escpos_raw or browser mode)
- Add printer.js with WebUSB and Web Serial support for direct browser-to-printer
- Add thermal print button in ticket modal with connect/print workflow
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>