- Updated the `active` field validation in `WorkflowSummary` to use `field_validator` for improved clarity and functionality.
- Enhanced error messages in `get_workflow_detail`, `download_workflow`, and `get_workflow_diagram` endpoints to provide more specific feedback when workflows or files are not found.
- Added exception handling for JSON parsing errors in `get_workflow_diagram` to improve robustness.
- Updated the database file `workflows.db` to reflect recent changes.
