Add Garuda

[madhu-sv]

Adds Garuda (https://github.com/madhu-sv/garuda), an open-source (Apache-2.0) coding agent with an OS sandbox (Seatbelt on macOS, bubblewrap on Linux), approvals for edits and commands, and an audit log. It works with Claude, OpenRouter or a local model server.

• Distribution: npx, @garuda-agent/garuda@0.16.1 (published with npm provenance from GitHub Actions), args ["acp"].
• Authentication: Terminal Auth (id garuda-setup). The client runs the setup in a terminal: garuda setup (args replaced) or garuda acp setup (args appended) both work. It asks for the provider, the model and the key, checks the key, and stores it in ~/.garuda/credentials (mode 0600, unreadable from Garuda's sandbox). With no setup, session/new returns auth required.
• Platforms: macOS and Linux. On native Windows, Garuda answers with a message to use WSL.
• Icon: 16x16, currentColor only.

Checked locally:

• build_registry.py: passes (garuda v0.16.1).
• verify_agents.py --auth-check --agent garuda: "Auth OK: garuda-setup(terminal)".
• Tested live in Zed 1.22: sign-in from the editor, then a session with no restart.