Added comprehensive troubleshooting guide for Docker image pull failures
in mainland China, based on Issue #168.
Problem:
- Users in China cannot pull Docker images from Docker Hub
- ERROR: load metadata for docker.io/library/...
- Timeouts and connection failures
Solutions Added:
1. Configure Docker registry mirrors (Recommended)
- List of working China mirrors
- Step-by-step configuration for Linux/macOS/Windows
- Verification commands
2. Use VPN
- Taiwan nodes recommended
- Global mode required
3. Offline image download
- Image proxy websites
- Manual import instructions
Both English and Chinese versions updated.
Fixes: #168🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: tinkle-community <tinklefund@gmail.com>