[Agent Client Protocol] support for custom agent

### Extension

https://www.raycast.com/Yukai/agent-client-protocol

### Description

I use custom agent in other tools (like obsidian) to connect to my customer acp agent.
For example it works with kiro-cli with these params:
`$HOME/.local/bin/kiro-cli acp --agent myagent`

### Who will benefit from this feature?

_No response_

### Anything else?

_No response_