Hello, I am a developer learning AI Gateway. I have an interest in the arch solution, and as I explore the source code and demo version, I have a few questions.

1. While reviewing the documentation, I noticed the mention of "Arch binds itself to a local address such as 127.0.0.1:9000/v1 or a DNS-based address like arch.local:9000/v1 for outgoing traffic" regarding upstream. Where and how should I configure this setting to allow such configuration?

2. I followed the pre-requisites and the instructions in function_calling > README.md for the demo version, but I encountered an API connection error in AI chat (I did set the OPENAI_API_KEY). To address this, I modified the address in function_calling > docker-compose.yaml as shown below, which made the chat work but only resulted in simple OpenAI chat, rather than the example-based chat functionality. Could you provide additional guidance on this?

chatbot_ui:
  ...
   environment:
     - CHAT_COMPLETION_ENDPOINT=https://api.openai.com/v1
     #- CHAT_COMPLETION_ENDPOINT=http://host.docker.internal:12000/v1
  ...