Add database query step (MySQL, PostgreSQL, MongoDB) #50
Description
Description:
Execute database queries and store results in variables.
Tasks:
- Design DatabaseQuery step type
- Add connection configuration
- Support SQL queries
- Support MongoDB queries
- Handle query results
- Add connection pooling
- Test with all database types
Acceptance Criteria:
- Queries execute correctly
- Results stored in variables
- Connection management sound
- All databases supported