Adds Task key to the output to back ref to it on callbacks/webhooks

src/crewai/task.py

@@ -373,6 +373,7 @@ class Task(BaseModel):
 
             pydantic_output, json_output = self._export_output(result)
             task_output = TaskOutput(
+                key=self.key,
                 name=self.name,
                 description=self.description,
                 expected_output=self.expected_output,

src/crewai/tasks/task_output.py

@@ -9,6 +9,7 @@ from crewai.tasks.output_format import OutputFormat
 class TaskOutput(BaseModel):
     """Class that represents the result of a task."""
 
+    key: Optional[str] = Field(description="Key of the task", default=None)
     description: str = Field(description="Description of the task")
     name: Optional[str] = Field(description="Name of the task", default=None)
     expected_output: Optional[str] = Field(