Added OPENCLAW-SETUP.md with comprehensive setup instructions:
- Three setup methods: interactive wizard, web UI, and manual config
- Links to get API keys from all major providers
- Pre-installed tools overview
- Troubleshooting section
- Gateway token information
The guide is now visible on the desktop when users first log in,
making it easier to configure OpenClaw without leaving the container.
Modified Dockerfile to copy the setup guide to the desktop during build.
Co-authored-by: Cursor <cursoragent@cursor.com>