Added a timestamp field to the SystemVariable model and updated the WorkflowAppRunner to include the current timestamp during execution. Enhanced node type checks to recognize trigger nodes in various services, ensuring proper handling of system variables and node outputs in TriggerEventNode and TriggerScheduleNode. This improves the overall workflow execution context and maintains consistency across node types.
refactor(api): Separate SegmentType for Integer/Float to Enable Pydantic Serialization (#22025)
This PR addresses serialization issues in the VariablePool model by separating the `value_type` tags for `IntegerSegment`/`FloatSegment` and `IntegerVariable`/`FloatVariable`. Previously, both Integer and Float types shared the same `SegmentType.NUMBER` tag, causing conflicts during serialization.
Key changes:
- Introduce distinct `value_type` tags for Integer and Float segments/variables
- Add `VariableUnion` and `SegmentUnion` types for proper type discrimination
- Leverage Pydantic's discriminated union feature for seamless serialization/deserialization
- Enable accurate serialization of data structures containing these types
Closes#22024.
