Added Facefusion face swapping service to the AI stack:
**Configuration:**
- URL: https://facefusion.ai.pivoine.art
- Image: facefusion/facefusion:3.5.0-cpu
- Port: 7865
- Container: ai_facefusion
- Volume: ai_facefusion_data
- HTTP Basic Auth protection
- CPU execution mode (GPU when available)
**Changes:**
- Added facefusion service to ai/compose.yaml
- Added AI_FACEFUSION_* env vars to arty.yml
- Created ai_facefusion_data volume
- Removed old standalone facefusion stack
- Removed ai/README-export.md and ai/webui-export.py
Facefusion will run on CPU until GPU server is available.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
