Agent Pointed Context: reference implementation and demo

Open reference implementation and live demo of Agent Pointed Context (APC): an application exposes three identifier-only channels to any agent connected over the Model Context Protocol (the person's view, a pin the person drops on a row or on a part of a computed figure, and the agent's presence on screen), and the person's own agent reads what a pin points at through its ordinary, authorized tools, joining it with what it already knows about the person. Three TypeScript packages (protocol, server, web) and Pulse, a synthetic SaaS analytics demo on Cloudflare Workers with one Durable Object per visitor. Live at https://apc.tineira.com.