Connect DeepSeek Harness (dsh) to Cursor and Codex

Key features

• ACP profileinitialize → session/new → session/prompt → streamed answer → end_turn (tested against dsh 0.1.0-rc.6).
• Connect DeepSeek Harness (dsh) to the Cursor editor and the OpenAI Codex CLI — as an ACP agent, an MCP server, or a headless worker.
• Cursor and Codex are ACP agents, not ACP clients — neither can load a third-party ACP agent today.
• The Cursor provider includes dsh-cursor-upgrade-gate.
• MCP serverinitialize → tools/list → dsh_health → dsh_delegate real task (tested against dsh 0.1.0-rc.6).