Introduce structure keys (#902)

* Introduce structure keys

* Add agent key to tasks

* Rebasing is hard

* Rename task output telemetry

* Feedback

src/crewai/agents/agent_builder/base_agent.py

@@ -1,6 +1,7 @@
 import uuid
 from abc import ABC, abstractmethod
 from copy import copy as shallow_copy
+from hashlib import md5
 from typing import Any, Dict, List, Optional, TypeVar
 
 from pydantic import (
@@ -162,6 +163,11 @@ class BaseAgent(ABC, BaseModel):
             self._token_process = TokenProcess()
         return self
 
+    @property
+    def key(self):
+        source = [self.role, self.goal, self.backstory]
+        return md5("|".join(source).encode()).hexdigest()
+
     @abstractmethod
     def execute_task(
         self,