I work on some proprietary codebases and can only use private AI services with them (currently MiniMax M2.1 and GLM 4.7). It all works great with both Claude Code and OpenCode agents, and I'd like to leverage the new agentic capabilities that are now in Xcode 26.3. I'm not seeing any option to connect to OpenCode, and both the Anthropic and OpenAI providers require an enterprise account (which I don't have access to). Are there any options that I'm missing here?