Feat: Agent Token or Request Limiting (#2041)

* Update routes.py, added token and request limits to create/update agent operations

* added usage limit check to api endpoints

cannot create agents with usage limit right now that will be implemented

* implemented api limiting as either token limiting or request limiting modes

* minor typo & bug fix

application/api/answer/routes/stream.py

@@ -76,6 +76,9 @@ class StreamResource(Resource, BaseAnswerResource):
             agent = processor.create_agent()
             retriever = processor.create_retriever()
 
+            if error := self.check_usage(processor.agent_config):
+                return error
+
             return Response(
                 self.complete_stream(
                     question=data["question"],