### What problem does this PR solve?
feat: add OperateDropdown
feat: send debug message #918
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
feat: fetch flow #918
feat: save graph
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
feat: Support for conversational streaming
#709
### Type of change
- [x] New Feature (non-breaking change which adds functionality)