Changes to GET `/api/v0/main-frontend/chatbots`

removed the required property items/use_tools from the response with the 200 status

added the required property items/enabled_tool_categories to the response with the 200 status

added the required property items/publicly_accessible to the response with the 200 status

the response property items/course_id became nullable for the status 200

the response property items/course_id became optional for the status 200

endpoint added