This PR adds support for using external agents in SSH projects via ACP, including automatic installation of Gemini CLI and Claude Code, authentication with API keys (for Gemini) and CLI login, and custom agents from user configuration. Co-authored-by: maan2003 <manmeetmann2003@gmail.com> Release Notes: - agent: Gemini CLI, Claude Code, and custom external agents can now be used in SSH projects. --------- Co-authored-by: maan2003 <manmeetmann2003@gmail.com>