docs: add comprehensive workflow creation and export guide

This guide documents how to:
- Create workflows programmatically via direct database operations
- Configure all supported block types (start, agent, api, function, response, etc.)
- Set up MCP tools and local file operations
- Export workflows to standalone Python services
- Run and test exported services

Includes SQL templates, block configuration examples, and troubleshooting tips.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: aadamsx