Removing LangChain and Rebuilding Executor (#1322)

* rebuilding executor

* removing langchain

* Making all tests good

* fixing types and adding ability for nor using system prompts

* improving types

* pleasing the types gods

* pleasing the types gods

* fixing parser, tools and executor

* making sure all tests pass

* final pass

* fixing type

* Updating Docs

* preparing to cut new version

tests/utilities/evaluators/test_crew_evaluator_handler.py

@@ -44,7 +44,7 @@ class TestCrewEvaluator:
             == "Evaluator agent for crew evaluation with precise capabilities to evaluate the performance of the agents in the crew based on the tasks they have performed"
         )
         assert agent.verbose is False
-        assert agent.llm.model_name == "gpt-4o-mini"
+        assert agent.llm == "gpt-4o-mini"
 
     def test_evaluation_task(self, crew_planner):
         evaluator_agent = Agent(