Two issues in Dockerfile.complete caused the nginx welcome page to appear
instead of the BiliNote UI:
1. /etc/nginx/sites-enabled/default had `listen 80 default_server` which
took priority over the custom config in conf.d/
2. The nginx config proxied / to frontend:80, but the Dockerfile sed
replaced it with 127.0.0.1:8080 where no service was running. The
frontend is built as static files in /usr/share/nginx/html/.
Fix:
- Remove /etc/nginx/sites-enabled/default in Dockerfile
- Change location / to serve static files directly instead of proxying
- Remove the frontend proxy sed (no longer needed)
- Introduced a `Dockerfile.gpu` for GPU-enabled backend setup.
- Added `docker-compose.gpu.yml` to utilize GPU resources via NVIDIA.
- Fixed Nginx configuration for GPU backend port changes.
