Read the current implementation and consider the following problem (vibe-kanban 25d8b973)

Currently, the HumanInput node yields a `HumanInputFormFilledEvent` event while form is submmited. However, for form level timeout, current no event about timeout is emitted. This makes the frontend UI not updated while the events of time out are sent to the frontend.

Analysis this problem, propose a way to resolve this issue.

api/core/workflow/graph_events/__init__.py

@@ -39,6 +39,7 @@ from .node import (
     NodeRunExceptionEvent,
     NodeRunFailedEvent,
     NodeRunHumanInputFormFilledEvent,
+    NodeRunHumanInputFormTimeoutEvent,
     NodeRunPauseRequestedEvent,
     NodeRunRetrieverResourceEvent,
     NodeRunRetryEvent,
@@ -61,6 +62,7 @@ __all__ = [
     "NodeRunExceptionEvent",
     "NodeRunFailedEvent",
     "NodeRunHumanInputFormFilledEvent",
+    "NodeRunHumanInputFormTimeoutEvent",
     "NodeRunIterationFailedEvent",
     "NodeRunIterationNextEvent",
     "NodeRunIterationStartedEvent",

api/core/workflow/graph_events/node.py

@@ -63,5 +63,12 @@ class NodeRunHumanInputFormFilledEvent(GraphNodeEventBase):
     action_text: str = Field(..., description="Display text of the chosen action button.")
 
 
+class NodeRunHumanInputFormTimeoutEvent(GraphNodeEventBase):
+    """Emitted when a HumanInput form times out."""
+
+    node_title: str = Field(..., description="HumanInput node title")
+    expiration_time: datetime = Field(..., description="Form expiration time")
+
+
 class NodeRunPauseRequestedEvent(GraphNodeEventBase):
     reason: PauseReason = Field(..., description="pause reason")

api/core/workflow/node_events/__init__.py

@@ -14,6 +14,7 @@ from .loop import (
 )
 from .node import (
     HumanInputFormFilledEvent,
+    HumanInputFormTimeoutEvent,
     ModelInvokeCompletedEvent,
     PauseRequestedEvent,
     RunRetrieverResourceEvent,
@@ -25,6 +26,7 @@ from .node import (
 __all__ = [
     "AgentLogEvent",
     "HumanInputFormFilledEvent",
+    "HumanInputFormTimeoutEvent",
     "IterationFailedEvent",
     "IterationNextEvent",
     "IterationStartedEvent",

api/core/workflow/node_events/node.py

@@ -56,3 +56,10 @@ class HumanInputFormFilledEvent(NodeEventBase):
     rendered_content: str
     action_id: str
     action_text: str
+
+
+class HumanInputFormTimeoutEvent(NodeEventBase):
+    """Event emitted when a human input form times out."""
+
+    node_title: str
+    expiration_time: datetime

api/core/workflow/nodes/base/node.py

@@ -17,6 +17,7 @@ from core.workflow.graph_events import (
     NodeRunAgentLogEvent,
     NodeRunFailedEvent,
     NodeRunHumanInputFormFilledEvent,
+    NodeRunHumanInputFormTimeoutEvent,
     NodeRunIterationFailedEvent,
     NodeRunIterationNextEvent,
     NodeRunIterationStartedEvent,
@@ -34,6 +35,7 @@ from core.workflow.graph_events import (
 from core.workflow.node_events import (
     AgentLogEvent,
     HumanInputFormFilledEvent,
+    HumanInputFormTimeoutEvent,
     IterationFailedEvent,
     IterationNextEvent,
     IterationStartedEvent,
@@ -649,6 +651,16 @@ class Node(Generic[NodeDataT]):
             action_text=event.action_text,
         )
 
+    @_dispatch.register
+    def _(self, event: HumanInputFormTimeoutEvent):
+        return NodeRunHumanInputFormTimeoutEvent(
+            id=self.execution_id,
+            node_id=self._node_id,
+            node_type=self.node_type,
+            node_title=event.node_title,
+            expiration_time=event.expiration_time,
+        )
+
     @_dispatch.register
     def _(self, event: LoopStartedEvent) -> NodeRunLoopStartedEvent:
         return NodeRunLoopStartedEvent(

api/core/workflow/nodes/human_input/human_input_node.py

@@ -7,7 +7,12 @@ from core.app.entities.app_invoke_entities import InvokeFrom
 from core.repositories.human_input_reposotiry import HumanInputFormRepositoryImpl
 from core.workflow.entities.pause_reason import HumanInputRequired
 from core.workflow.enums import NodeExecutionType, NodeType, WorkflowNodeExecutionStatus
-from core.workflow.node_events import HumanInputFormFilledEvent, NodeRunResult, PauseRequestedEvent
+from core.workflow.node_events import (
+    HumanInputFormFilledEvent,
+    HumanInputFormTimeoutEvent,
+    NodeRunResult,
+    PauseRequestedEvent,
+)
 from core.workflow.node_events.base import NodeEventBase
 from core.workflow.node_events.node import StreamCompletedEvent
 from core.workflow.nodes.base.node import Node
@@ -245,6 +250,10 @@ class HumanInputNode(Node[HumanInputNodeData]):
             return
 
         if form.status == HumanInputFormStatus.TIMEOUT or form.expiration_time <= naive_utc_now():
+            yield HumanInputFormTimeoutEvent(
+                node_title=self._node_data.title,
+                expiration_time=form.expiration_time,
+            )
             yield StreamCompletedEvent(
                 node_run_result=NodeRunResult(
                     status=WorkflowNodeExecutionStatus.SUCCEEDED,