b64b6b8a79
- Added ACP (Agent Client Protocol) mode for headless agent operation via --mode acp flag. - Integrated Agent Client Protocol SDK with session management, streaming communication, and event mapping. - Added ensureOnDisk() method to SessionManager for immediate session persistence without requiring assistant messages. - Changed session persistence to use atomic file rewrite for unflushed sessions. - Implemented AcpAgent class with session management, prompt handling, MCP server configuration, and event streaming.