Add autonomous routing system by ChatGPT⚡️

[uezo]

ChatGPTRouter is a new autonomous router powered by ChatGPT.

• Use ChatGPTContentSkill as default skill for just chatting.
• Use user extension skill that extends ChatGPTFunctionSkillBase when ChatGPT returns function calling.
• You can also invoke the specific skill explicitly by setting intent to request.

See also the newly added demo that switches skills below autonomously without any routing configurations but just attaching skills.

• Chatting
• Weather(dummy)
• Reminder(dummy)