- Set Start node isRequired: false since entry node validation is handled by unified logic
- Remove conditional skip logic in checklist since Start is no longer in isRequiredNodesType
- Cleaner separation of concerns: unified entry node check vs individual required nodes
- Eliminates architectural inconsistency where Start was both individually required and part of group validation
Complete workflow liberalization following PR #24627:
1. Remove Start node deletion restriction by removing isUndeletable property
2. Fix draft sync blocking when no Start node exists
3. Restore isWorkflowDataLoaded protection to prevent race conditions
4. Ensure all entry nodes (Start + 3 trigger types) have equal deletion rights
This allows workflows with only trigger nodes and fixes the issue where
added nodes would disappear after page refresh due to sync API blocking.
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
