v0.20: Project Owners and cross-project messaging

Every project can now designate a Project Owner — and owners can discover other local projects and message each other directly.

Highlights

• Projects — designate an agent as the Project Owner.
• Cross-project messaging — Project Owners can discover other local projects and message each other.
• Plugins — new Plugins page for Claude provider plugins: enable or disable each plugin globally or per project.
• Event bus — persisted event history is pruned after 30 days.
• Subscribers — the "Send Message to Agent" action can target a different agent by name.

Install or update with npm install -g devchain-cli.